i have both. you cant compare the sound of a rev2 to the A4. the rev2 is really biggggggggerrrr and have really much more possibilities in term of sound design and modulation.
however the Big plus of the A4 is his perfect and so Good sequencer with Plock!!! (and the beautiful reverb)
Wow! Thank you both for your input.
I see the Rev2’s mod matrix:
22 sources
52 destinations
That’s more than the A4II?
The rev2 and other DSI synths mod matrix is pretty much unrivalled among hardware synths.
Obviously the A4 has the better sequencer though
When it comes down to the mod matrix the Rev2 is really a beast on it’s own and not comparable with the A4. But for a complete package (which includes of course the sequencer) the A4 also takes it’s strong stand.
In the end I think it comes down to usability. For me the endless encoders and the GUI system on the A4 wins hands-down. On the Rev2 you never know at which setting a parameter is and if it will jump when you turn a knob (mostly no endless encoders and no way to see parameter values BEFORE changing them after loading a patch).
this is true for the P08, but with the rev2 they added a “show” button that you can hold and turn the knob of interest slightly and it will show the value without changing anything.
Oh, really? Sorry, then I missed that improvement completely (putting the Rev2 again on my take-a-closer-look list).
The only thing keeping me from ordering a Rev2 is the pack of a high-pass filter like on the P6.
Rev2 does have a resonant high pass filter in the effects options. So when used, you can’t use any other effect, but I’m glad it’s there none-the-less.
That’s nice, but not as useful as having it per-voice with key tracking and modulation.
While the cash was growing for the A4II the Rev2 got my attention (the Pro 2 got it first when visiting DSI’s website). Options like CVs and analog inputs are things I want the Rev2 can’t offer obviously. I’ll keep the Rev2 in my mind and compare it with the Novation Peak, another little beast.
Also is there a place in the manual or somewhere else with a “map” of the A4II’s mod matrix and all its routing options?
Thanks again for all the replies folks.
There’s not really a mod matrix on the A4 envelopes and LFOs can be routed to just about any parameter of the synth voice(two destinations for each).
Here you go:
If you want the synth with the most mod destinations/sources, you should consider the DSI P12. But the most options and possibilities are definitely a DAW and a few GOOD plugins! But IMO hardware is much more fun. Whatever you buy (A4,Rev2, P12) there are all awesome.
“Ask and you shall receive the mod matrix” 
DSI’s Mod Matrix. Pro2 vs P12
Your point of having fun is why I am looking forward to get the A4II, and its “limitations” compared to a DAW. DAWs are getting more and more powerful, but you still have to use a mouse, for the most part. I use Reason. I love it. A bit of hardware is needed to break the routine, imho. P12 and Pro2 were my choices but if had to go hardware I would have to go analog.
The A4MKII is an excellent choice for having fun OTB. Where all my other stuff is more or less hardwired wherever it is (some older keyboards like the K5000S and an Ableton Live+Push2 setup), the A4MKII is my mobile unit to lay down some ideas (melodies or sounds) on the couch, in bed or even outdoors.
Oh, looks like the Pro has much more! Pretty hard decision, but both are great synths. What genre do you have in mind? Do you really need the parameter locks? Do you plan to get a midi controller Keyboard? If you want the sequencer, then buy the A4 or a Octatrack, to use the sequencer for Parameter locks and all the other elektron stuff on the rev2 (of course this would be extremely expensive). The A4 has FM options, the LFOs can go into audio rate, you can do AM, the sound can go from very clean to think and IMO warm. Even one voice (2xDCOs + 2xSub) can be massive. For analog bass it’s always my favourite. I always use it like 4 monosynths. The peak filter can even achieve even some formant-like sounds if you give him some movement (or boost the bass!). If you music is more like 80s, pop, traditionell or something like that, go for the REV2. But if you want to do fast stuff like, tech, house, trance, glitch, drones or ambient I would go for the A4. The a A4 can much more, and can be a awesome groove box to. The song mode/arranger is awesome, the fx are very good. But the sound isn’t as warm as the REV2. Definitely get a small midi controller like the Arturia Keystep for playing one the A4. The keyboard on the A4 is great but it’s just one octave and I always come up with better ideas when i connect a midi keyboard to it. The A4 can do percussion/drums but it is really basic, if you want to make samples with drums already in it, you should get a drum machine or a DAW.
The Rev2 interface is in another league compared to the A4 also, if that is a factor to consider
The forum is so welcoming (and pretty well designed) I think I may have to get the A4II just to have a good excuse to chill out here. No choice 
One tool is what I am looking for. 80’s, deep house, drone, imaginary soundtracks.The Rev2’s source/destination interface is so cool and fast. I wish the seq was deeper like the Pro2.
Through the global menu you can choose how you want the pots to behave:
RELATIVE: changes are relative to the stored setting
PASSTHRU: Turning the pot has no effect until after the edited value equals the preset value
JUMP MODE: turn a pot and the value jumps immediately from the stored value to the edited value