looks like that site now has the IPV5 for 35 bucks. Still an excellent deal.
eCig.com is currently running IPV D3 for $29, if you're looking for a smaller, one batt device...
There's really no "best" though. It's whatever you like. Popular reliable brands in my opinion include IPV, Sigelei, SMOK, Joyetech, eLeaf... In that order... again just my opinion.
I'd get any tank that takes Atlantis/Triton style coils. There are so many tanks that fit them, so you can walk into any vape shop and most likely get a coil that will fit if you're in a pinch. Herkales, Aspire, Starre, Playboy, Vapeston are some brands that fit this category.