I can't really offer much of a comparison, because I've only tried a 200 combo once, briefly and in a store. That experience might have been what sold me on the v3 Rumbles, actually, because after that I sought out and found the used 500 head. Not specifically remembering what the 200 combo sounded like, my guess is that it's very similar to the set-up I have, except that the 500 has extra headroom (cleaner low end, etc.).
Apart from two great Ampeg combos (little BA110 practice amp and 100 watt Rocket Bass), I prefer separate heads and cabs, partly for the ability to mix and match, and partly because I'm superstitious and obsessive about having spares in case of equipment failure! (At the gig pictured above, I had a Trace Elliot ELF in a backpack for my spare, plus another Jazz Bass lying on a towel on the rock shelf behind me. And extra cords, etc., etc.)