I was trying to choose between these two types and I went with the FAL. I wasn't looking in the price ranges you're talking about though. The Century FAL ran me about $500.00 - $600.00, while the G3 at the time would have cost me around $350.00.
I decided on the FAL for a number of reasons.
First... the magazines are WAY cheaper, as low as $1.99 each in some catalogs.
Second... the FAL is used by NATO allies, and as far as I could tell when I was researching the subject, parts are more common for them from companies like Tapco.
Third... The G3 has a fluted chamber. The only drawbacks I can see with a fluted chamber are that they are probably harder to clean, and I've heard that commercial .308WIN ammo may be too hot and the brass shell can shred apart inside the fluted chamber because it isn't reinforced all the way around the shell.
Surplus NATO .308 ammo is ok for the G3 but the commercial hunting loads are more powerful. I was afraid that eventually the surplus .308 may run out and I'd be forced to buy the commercial stuff. This isn't an issue for those who reload, and many say that they've used the commercial stuff with no problems. But I have seen pictures of shells blown apart inside the fluted chamber of a G3 and it scared me.
After saying all of this you should know that I've never handled a G3 type rifle. My limited knowledge comes only from reading about them.
I really like the way the FAL breaks down. It is a very simple design and there seems to be a much larger fan base for the FAL among those who can afford them.
The DSA FAL is supposed to be one of the most accurate and well-made semi-auto rifles around. But I'm happy with my Century. I had to turn the gas knob to the most closed position for Argentina surplus ammo and it was shooting sweet. I like the idea of the adjustable gas chamber for various loads. It's easily adjustable with one hand. I'm not sure wether the G3 type rifles have that feature. Good luck in your decision.
