I've found a quite good review of the DN-S5000, i hope it can help you:
The same criticism of the DN-S3000's platter control system can also be applied here - namely the problems with torque and buffering confusion. The issues with the scratch sound and 45rpm platter speed are more open to user interpretation and depend on their demands. A one-stop vinyl emulation system it is not. The scratch sound has seen some updating since release and has definitely improved. There is generally a slight digital sound to the scratching, accentuated on higher pitched sounds. Also there are some slight differences between the two stabilizer / shaft types. On the original stabilizer the scratch disc can feel a bit loose because of the way it fits to the stabilizer. This can affect performance slightly so the make-shift solution to this has been to run tape through the centre hole of the scratch disc in much the same way you'd do with vinyl on a regular turntable.
Much of the bread & butter features of the DN-S3000 are on the DN-S5000 in one way or another. So what do you get for your extra money? Well you gain an extra platter effect - ECHO. This is a BPM-synced effect with selectable time paramters of 1/2, 1/1 and 2/1. It creates an, ermmm, echo effect - probably much like you would expect! But how does it know the BPM you may ask? Well, yes, the DN-S5000 features an onboard BPM counter with automatic, tap and manual input modes. This follows the usual tradition of hardware based automatic BPM counters in being a bit flakey with complicated rhythms. A few taps of the BPM input button should get things in the right area (or at least good enough for the BPM synced required areas of the deck). There is a selectable lever that toggles the platter controlled audio output from both directions to just forward - meaning you can have the player mute any backstrokes. So you can perform stabs without even using the fader. Probably won't see much use from those of us proficient with faders. Some may like this feature though (will also give you an indication of how fast you should be able to stab providing your fader hand can keep up!). The real power differences lie in the hot-start/stuttering/sampler capabilities, combined with the alpha-track facility.
Alpha-Track: What is it, how does it work, and what can you do?
Through some very clever memory and buffer tricks you can play and manipulate two tracks from the same audio-cd through separate outputs (you can bounce the alpha-track audio down to the main output if needs be). There are separate alpha-track controls for play, cue & pitch bend with the parameters dial doubling as the alpha-track pitch control. The platter control is also switchable between main, alpha, sampler and search modes. There can be a lot of initial head-scratching trying to get the alpha-track to do what you want it to, and to be honest I think the manual supplied with the unit is virtually useless. Essentially you jump into an alpha-monitor mode to select the track you want from the cd. The key is to then leave this alpha-monitor mode once you have the track and cue point you want, otherwise you will end up doing a cue or play change depending on what is happening on the main track. Once you are running smoothly though, there is a nice feeling once you've mixed two tracks from the same cd seamlessly together. So what other tricks does the larger memory and alpha-track bring? Well the easiest way to explain it is that the DN-S5000 has 4 pads available for various uses (A1,A2,A3,A4). These have a selectable configuration:
1) 2 MAIN hot-start/stutter/loop points + 2 SAMPLER BANKS
2) 2 MAIN hot-start/stutter/loop points + 2 alpha-TRACK hot-start/stutter/loop points
3) 4 MAIN hot-start/stutter/loop points
So you get a lot more flexibility than with the DN-S3000 which has just 1 sampler bank and 1 hot-start/stutter/loop point. The same A/B trim or move facility is available for each loop point, as well as the SPLICE function which means the player effectively skips over the loop you set up. This means you can now remove that annoying section of a track that you've always wished wasn't there! Also the fact that you have a separate alpha-output means you easily sample a loop of what is already playing and then scratch it over the top using the full control of a separate mixer channel.
The alpha-track also brings another BPM synced feature - MIRROR MIX. This basically does what you could do by hand but significantly quicker and more accurately. It sets up the alpha-track playing what is on the main track, but allows you to delay it by predefined beat amounts (1/8, 1/4, 1/2, 3/4, 1/1 & 2/1). Hence it relies on having an accurate BPM reading to get a clean delay time if you want to quickly cut between them on your mixer.
MEMO & MP3 compatibility
The DN-S5000 has similar MEMO capabilities as the DN-S3000, except that it can store alpha-cue and A/B-2/3/4 points in each memory bank section as well. MP3 compatibility is here, but suffers the same restrictions as those found on the DN-S3000. The extra power under the hood of the DN-S5000 has no extra benefit for MP3 use - i.e. alpha-track is NOT available whilst using MP3 and only 1 hot-start/stutter/loop point can be used. If you are intending to use this primarily for MP3 then perhaps the DN-S3000 would be a better alternative. Also seeing as the DN-S5000 is Denon's flagship tabletop cd player, it is a shame (and widely voiced criticism) that there is no removable MEMO storage unlike the Pioneer CDJ-1000.
Although it is 'virtually' two cd players in one, it isn't quite. It hasn't got two platters or two displays. Also depending on what is being used at the time, other features will not be available due to conflicts in memory use. There has been more than a couple of occasions where i've tried to do something only for the display to flash at me and tell me it can't because the sampler or alpha-track is playing. However, the alpha-track feature is unique to Denon and is quite an innovation. Even if you never use the alpha-track you've still got a very fine player with 4 hot-start/stutter/loop points (though someone who buys the unit and never uses one of it's key features needs their head examined). The alpha-track feature does take a significant amount of time to learn properly and coupled with the poor manual there will no doubt be a few moments of frustration. You need to be in it for the long haul. I also believe a significant proportion of people will never get the most out of their players as there are less obvious features and tricks that are scarcely covered. If you are looking for a simple "no frills" player then it probably isn't the one for you. The alpha-track and multiple loop points, combined with the two samplers open up a huge amount of creative potential. I'll be honest in that after having a DN-S5000 for over a year I'm still not probably using it to it's full potential. Also because the unit is quite compact a lot of the buttons have double functions and there is a certain amount of menu navigation which may not suit some people (I always forget the MIRROR MIX function even exists!). If you sound like the sort of person who is willing to spend the time and effort learning the unit properly then you will be rewarded with what is the most advanced, innovative and feature packed player on the market. There is no other unit that offers as much at such a high quality.