It depends.
I purchase from:
Hamworld in Talledega. Generally good prices on what they carry or have in stock. Real nice guys to deal with.
RandL. Good prices. Quick ship.
DXengineering. Will combine autoparts(Summit Racing) and ham stuff to meet the "free shipping" threshold.
HRO. About 18 miles from my Atlanta QTH. Nice return policy, good prices.
Gigaparts? No. I don't get a good vibe.
Mostly buy gear from other hams.
73, -bob ah7i