I would guess that a typical car AC compressor would absorb about 2-3hp, so that's less than 1½% of the power available at the flywheel. So I very much doubt you would notice it.
Mk 6 GTI, 3 Door, Manual, Carbon Grey, 18" Monza Shadows, RCD510 with Dynaudio + DAB, Xenons, Winter pack, Storage pack, and Mudflaps