Dean-o

I am going to have a C1 or C2 cam installed in my 99 SS Camaro and I am leaning towards the C1 because it has less lift than the C2 which has .581 and with single springs on my stock heads I feel more comfortable with the C1. My question is how much power difference is there between the two? Am i really losing much by not going with the C2 vs the C1? Thanks.
PS - I have all the normal bolt ons : airbox,K&N filter,ported MAF, long tube headers, high flow cats, 3" y-pipe, 3" exhaust cut out.