I am a Rev2 owner. I’m coming to realize that my Rev2 is more feature rich than I need, but simultaneously it has a smaller sweet spot than my Moogs. I don’t have the ability to play with both synths in store, and I don’t believe there is a wrong choice. But here is my takeaway from every clip I’ve heard:
OB6, warm but punchy. Great low end
P6, softer, less defined low end, but beautiful top end sheen.
I’m leaning P6, because I believe the Moog’s I have will carry the lows, but there is just a string like quality I love to the OB6, but I love the soft but brassy prophet color....decisions, decisions.......
I'm not sure if you already made a decision, but now that I own a P6 and can fairly compare it with the OB6 side-by-side, I can give a definite recommendation for the Prophet 6 as the board to own,
if you must choose only one.
Don't get me wrong, I adore my OB6. I bought one for a specific purpose -- because I was so satisfied with the Rev2's ability to provide that fat classic Prophet sound, I wanted something that could specifically address the lack of Oberheim sound in my setup.
Both of them inspire me and make me want to play. The OB6 is essential to my setup but it is very "niche" in the sense that what it does, it does very well...but the spectrum of what it does well is much narrower than the P6. It is sort of like this little demon that is known to misbehave and doesn't always do what it's told, but is guaranteed to keep things interesting wherever it goes.
In almost every category I've tried, including bass, the Prophet 6 seems to do better at creating gorgeous and usable sounds. If a punchy low end is what you're after, the P6 is better choice IMO, and that was a something that I did not expect to find. The P6 just seems to sound great no matter what I throw at it.
As someone who likes to experiment with genres like darkwave, John Carpenter soundtrack-type stuff, I will never part with my OB6. But there are times when holding down a simple 3-note chord sounds disappointingly harsh on the OB6 because the natural drift between voices is so severe.