Theres nothing wrong with buying this guys ecu, its already ready already... But there's no sense in wasting extra money if you can just do it yourself. You can goto radio shack and for a few bucks you can have the stuff to use the ecu you already have. Then all you have to do is get an eeprom burner and make yourself the right chip.
Theres no real problem if you're semi computer literate, all you have to do is get an eeprom burner from ebay or anywhere (you could do it at a college if they have one *and* you go there...) and the PGMfi website is very comprehensive, all you have to do is download some software and burn the chip they have most of the stock maps posted and I'm sure the b16 is on there; not hard at all. And if you ever have some modifications down the road, like a turbo or something else you have all this crap already, so you can do it again for the price of a blank chip.
I would have to agree with the others, an ebay chip may or may not work so great for your car, a generic chip probably won't work as well as the one that you're supposed to have. And if you do it right, you don't really need a vafc, but it could still be handy. If you don't have alot of modifications (I/H/E) the stock map will work fine, and you can make modifications to it easily if you want. The programs on PGMFI are easy to figure out.
HTH