Personally I prefer the older models, they're much more raw, exotic, and aggressive looking. Of course, no power steering.....A good thing except in traffic where you shouldn't be trapped anyway. , and you hear complaints about the dash being too high...There is a conversion for this though. I know the chain tensioners need to be upgraded, and of course you want to know what the status of the clutch is. Electrically there aren't any major issues, some have spoken about grounding problems, but it's not serious. If you get one well sorted out you'll have less problems than a 6.0 with it's AWD, check engine lights, clutch rod breaking, leaking front shock and just all around sophistication. There is more expertise online with the earlier models since allot of guys have done their own work on them so you'll have good support. I don't know how you feel about wrenching on your car, but some ability and willingness is very helpful.

As far as performance, if you plan on just using the car occasionally as a departure from the normal grind of day to day driving, you'll be very satisfied. I've never bought into going the extra mile and expense just for horse power alone.

Lastly, an earlier Diablo is fully depreciated, and is the best bargain out there. That's my pitch for an early model, it's all that is Lamborghini, and you'll have allot of money left over just in case you have a nasty surprise, which is always possible with any exotic.