If you want to start mining right now, the HD7950s are the way to go, and they'll be useful for mining Litecoins even after Bitcoin reaches ASIC saturation.

By the way, $3400 seems pretty pricey for 5 of those cards and a box...the 7950s cost ~$320 each. You could save a lot by building the rig yourself. But anyway, if you decide you want to go this route, make sure you can support the 12+ amps it will draw. Also be aware that you won't see a return on investment for at least a year.