First of all, the idiots that think Charizard is better must need thick
glasses.  The reason that they do is that a full pumped Charizard will always
beat a full pumped Chansey. Big deal. Here is why Chansey is awesome.

    I can only think of one card that can screw a fully pumped Chansey on some
occasions when fully pumped, Kangaskhan.  If Kangaskan gets Comet punch to do
forty damage, which is average, Chansey can't Double edge and kill it without
killing itself.  Of course,  there are lots of Pokemon that can finish
Kangaskahn off, but you still lose if it's one prize to one prize. I know that
some Lizard-lovers are going to say "Big deal,  Charizard can still win." Well
the reason I compared these 2 is that they're both BASICS!
    
    So what if your lizard beats the big egg thingy?  While Charizard powers up
to do it again, you only need to deal 40 damage over 1 or 2 turns to KO it
(which means even MAGIKRAP could do it, imagine the embarrassment) So you lose
the Chansey and the 4 energy, while your opponent loses the whole deal that it
used to get Charizard out, plus any enrergy. So you lose 5 cards while your
opponent loses 2 or 3+ 2 - 4 cards for a total of 4 - 7.

    I hope this has cleared it up for some people.