I normally use Treecko all the time, twice I used Mudkip, after a while I left it in the PC storage. I never liked Torchic's design at all.
When I had my original Sapphire game for GBA, I use Treecko, don't know what happened to it, now I play GBA games on the emulator (I can save the game many times and decide which one to play on)
oh yes, I remember, just started playing it again and choose Treecko (with a really unusual Pokemon nickname- Karekezi) again.