For bluetooth, I would go with class 1 devices.
You might also consider using Xbees (the 1mW ones will be fine), especially if you need to do two-way communication. If you're just sending signals from a laptop with bluetooth, you would just need one bluetooth serial adapter, but to do two way, you would need two. The xbee solution is about $90 for two-way communication, compared to $120-140 for two class 1 bluetooth adapters...
If you give us more info about what you're going to do with the wireless connection, we can better point you in the right direction
