The differences in performance between the two generations are minimal. As you point out the G2's have TRIM support which OSX currently lacks (although one day might support it). However, the Intel drives hold up very well under heavy usage, minimizing the need for Trim compared to competing drives.
The G2 160GB drive does have somewhat better sequential write performance but the two generations of 80GB drives are nearly identical.
The big difference was the move to 34nm NAND which was supposed to dramatically reduce the cost/price of the G2 drives... but so far, that hasn't really materialized on average street prices as you are seeing first hand.
It's really your call... for $40, I'd probably go with the G2 just for the potential of future Trim support and perhaps better firmware support going forward.