Every car model is good in the right hands. One person will enjoy and do well with one car over another. Test driving cars at the track can give someone an idea but seeing that car is set up to the owners driving style,if the tester doesnt like it because of that setup,he might not buy it.
Ive enjoyed my X3. Ive raced the Hyper 8.5,9 and now HN X3 and all were solid cars for me. I have a friend that races the AE car and its a tank because he isnt the cleanest of drivers. But my X3 has been tested and held up as well to the abuse Ive given it.
Sadly,Ofna and its brands do not get the credit they deserve at most tracks and from most drivers. Its long overdue for sure and will come someday. But until then,those of us that drive it will be more then happy to prove people wrong.
As for parts. Not all shops can stock all parts for every car. Ive seen some that only carry parts for 2 or 3 cars. No matter what brand you go with,chances are you will have to go online to order items at some point. Nitrohouse.com and AMainhobbies.com are your best choices when it comes to replacement and upgrade parts.