Oh, well, it was directly after discussing the movie.
A good buy? To be honest, probably not unless you can get parts cheap, probably can, but I've heard some parts can be hard to find. Late 70s were not great in performance, though the Birds were decent compared to the 'Vette at the time in at least one category.
"The WS6/W72 combination quickly established the 1978 Trans Am as the "King of the Hill", long before there was such a thing a a Corvette ZR-1. Magazines loved the car and the Spring 1978 issue of Road Test magazine squared off a Z28, a Corvette, and a Trans Am in a street fight. The T/A was clearly chosen as the easiest car to drive fast.
As a result of the test, it was reported that it took 15.2 seconds to cover the quarter mile, going through the traps at 93.4 mph. It could spring from zero-to-sixty in 7.2 seconds and had a terminal speed of 123 mph, a full 600 rpms over the redline of 5000. In braking, the 3720 pound T/A test car took 149 feet to stop from 60 mph. In a circle, the Trans Am could generate .83g of grip which matched the test Corvette and was well beyond the .76g the Camaro Z28 capable of."
http://www.iwaynet.net/~gl&lisk/1978ta.html
Interestingly, the TT Trans Am of 89 would best the 'Vette.
I have never heard the Firebird to be very reliable. But if you like the looks, feel you can afford any needed restoration and the particular vehicle has a good history, I see no reason to not buy it if it fills your needs.
Frankly, though, if this is to be your daily transportation and you intend to be on extended trips, or just drive long distances, I would not buy it. I think it's best suited as a hobby car or fairly inexpensive transportation until a car of better quality can be affordably owned and maintained.
But I am no expert.
Ok, Hooligan, your turn.