I have two Prophet '08's, and both have encoders. One synth has the "encoder problem," and the other doesn't. There's a simple treatment for the problem that doesn't cost a dime. Ask DSI, and they'll send you at no charge a little tube of deoxit. Applying this to the encoder housing solves the issue in many cases, but not all.
I don't find the encoder problem to be a major issue. The fact is, you can adjust any parameter using the small buttons to the right of the "Param" knobs. This moves the parameter slowly - one digit per press - which obviously could be a problem in live situations. But if you're working entirely off of programs, then there is no problem. There's also the possiblilty of programming a parameter to be controlled by the modulation wheel. So, there are ways around the problem. But I think it would be ridiculous to write off the P08 merely because of the encoder issue. The truth is, knowing what I do, I'd still buy a third one to use as a mono synth if I could afford it! The more the merrier.
In my opinion, the ideal synthesizer panel looks like a Minimoog's - large knobs that are easily adjusted and calculated by the lines around them. But the P08 encoders are also easy to work with. Granted, I'd like to try the potentiometer edition, but that's not because the encoders are unbearable. And if I had known about the encoder problem, I still would have gotten my two P08's. The fact is, if you research every synthesizer and read as many user reviews as can be found, you'll eventually come across problems with every instrument. Again, look at the Andromeda. If I could make a list of all the complaints made by users on that one! Yet, it's still an excellent instrument, and nearly everyone - including myself - would love to have one. In fact, just to prove it, if anybody would be willing to send me $3,000, I'd be willing to buy an Andromeda.
