I used Piplup on my first play through of Pearl, as I was brand new to Pokemon and it was recommended. I then used Turtwig on my second and finally Chimchar on my third. If I started again on Platinum, I'd probably do a 'eeny,meeny', all of them are good in game.
I got Diamond and Platinum. In Platinum my starter was Piplup, who has fully evolved, and in Diamond my starter I was Chimchar, who is now an Infernape.
My first 4th Generation game was Pearl Version, in which my starter was Turtwig. I then got Platinum, and my starter was Chimchar. I like them both, better than Empoleon when I eventually had one. Although Infernape is generally just the best :P
On my platinum, first run: Turtwig. Second: Chimchar. I'm gonna restart my Pearl soon, guess who will be my starter? Piplup! Empoleon have such a badass name, typing and design!
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