I think that if I only raced stock I would probably switch back to the TC3. The track I race on is small indoor carpet and I think the TC3 has a small acceleration advantage over the XXX-S. The Losi seems to roll through corners better when set up right so an large tracks the cars should be more equal. In Mod I think the ease of driving with the Losi makes it a better car for me. All this being said I did manage to TQ and win our region champs in the stock class over TC3's and Mission's, there were faster cars in stock but they never managed to get good starts or clean runs. I just ran clean and reasonable fast all weekend. All of the cars out right now have pros and cons, it depends on which fits you the best.
Chad