Yeah, I used Cricket and their USB wifi card. Worked great for me and I was streaming live level2's from through a prop firm's software + Etrade Pro. Never had anything 'bad' happen due to latency or anything.
And if anyone isn't familiar with Cricket, they don't even HAVE a reputation of having good signal, good features or good anything. But the fact is - I only needed to be in 1 of 2 places ever when I was trading - so if Cricket had signal in those two places that was great, which it did, so it was great.
Also there is no 2-yr contract or cancellation fee with cricket. So it may be ideal especially if you are on the fence.