I'm a fond user of the starters to be fair, it's not until late on in the game that you usually find a decent replacement for them by which time you've already trained them up to the levels needed to beat the game. I've done it a few times, however, without using my starters. I think I used a Bagon one time, Sneasel a couple of times, Venonat a few times too and.. I want to say a Charmander in either Hoenn or Sinnoh, I can't remember which. I'm sure I've done Scyther, Elekid, Poliwag and Phanpy too.
Sneasel was a brilliant starter, probably because mine had eggs moves from my competitive Sneasel of Ice Punch, Night Slash.. nice base power moves at that level. As overpowered as Hyper Fang Rattata is at that stage of the game. Venonat wasn't too bad either, nice and fast levelling up.