If you want excellent reliable magazines that are also inexpensive:
Go to the midway usa sight and order the mecgar 8 round magazines they come in either blue or stainless I have some of both, and they are excellent, as good or better than the Wilsons which I also own several of.
They only cost $12 for the blued, and $15 for the stainless.
If you are a traditionalist they also have 7 rounders as well.
I'm with Master Blaster, the best cheap mags going are the MecGars from Midway. Stay away from the flush fit 8 rounders, and any 'bulk pack' MecGar (like found at CDNN). The 7 round flush and 8 round extended mags that are marked MecGar on the body are excellent.