How to check if an 08 is the PE edition, and any other suggestions buying used?

[proteus-ix]

Hi guys, I've run across a pretty good deal on an 08 desktop but the seller didn't seem to know off the top of their head if it's the PE edition or not, so I'm a little wary.

How can I verify if it is?  Is it just a matter of travel on the knobs, or could they just have installed the knobs and not actually soldered the connections etc?

Any other pointers to check it's condition before buying? 

I wasn't really planning on getting anything else for a while, but this is too killer of a synth for this price, and I feel bad letting it suffer in a bad home.   

[Sacred Synthesis]

Check for detented potentiometers (they "click" as you turn them) and parameters that have a limited range, rather than continue to infinitely turn.  For example, the Low Pass Filter Frequency parameter should stop when the line on top of the knob is at about 5 o'clock.