I have only owned the 007 and the 008.
Both are fantastic cars. The only advantage I can see with the 008 over the 007 is in my opinion the car is super easy to get along with.
By that I mean. The base build (set-up) is super easy to drive and when you do try some set-up changes the car reacts very well with no drastic changes that I have seen. It seems that everything I have try has always been a positive.
The 007 seemed just a touch sensitive to changes for me. But is still a killer car. And you should jump on one if you find one in good shape.
Heads up though. Just because someone says its only been ran one time and then shows a pic of a nice lookin chassis does'nt mean its true. I have seen many carpet cars that had been totaly whored out on carpet tracks that still looked new on the bottm of the chassis. Look for things like bent bulkheads, bent axles, and cracked shock towers. At the price of XRAY parts, you don't want to buy very many for a used car if you dont have to.