Well this is a sorta silly question your asking. It really just depends on who you are and what your personal preference is. They in fact all have the same base stats, it just depends if you care about Attack, Defense, or Speed. Chikorita has an excellent Defense, but it is weaker during the first 2 Gyms considering their is a type disadvantage. Cyndaquil is good with Attack and most likely speed too if yours is a Timid nature. And Totodile is a fast lean creature.
It really just depends on your personal preference. I wouldn't suggest asking this again, mainly because it is a choice we all have to make in the games, in the end it doesn't matter what other people think, it depends on what you think.
If you want more information on the similarity and differences between the starters go to Bulbapedia. Again, it entirely depends on your personal preference.
Now as to answer your question on what I chose, I picked Totodile, simply because I love the way it looks, and the fact that it does pretty well for the first 2 Gyms. I'd always picked Cyndaquil in the past but I wanted to change it up a bit. Also it is hard to get Water types in the beginning of the game.
I hope my advice helped.
With all regards,
-ChrisTom