Participate in a group buy. USB miners won't ROI, and unless you have the thousands you need for your own miner, you best off share the exposure with others.
Group buys seem extremely risky to me, why not cloudmine instead where you can at least be in control of your own hashing?
I should mention that the ROI on both is crap, just asking.
The pricing is closer to at cost on group buys, whereas cloudhashing is very overpriced and require contracts. With bitcoin prices going up, many GB can ROI in USD. If you are looking for USB miners, check out