Experience Penalties?

[Krait]

Krait here, noobin it up again.

I can see on the p99 wiki the racial experience penalties but I don't see any class penalties despite other posts mentioning it. Can someone break down all the penalties or point me to where it is already done? Does it stack or is it multiplicative?

I also have questions of the effect of these penalties? Are they noticeable? Are they truly made up for by other balance or will they really make it take longer to level? Will groups out level me to the point I'd need to re- group lower?

Thanks,
-Krait