I've shot bows both ways, and to me it is a toss up. The bow I've hunted with most this year does Not have a loop. It doesn't make me any more/less accurate to have a loop, and it does change the felt draw length of the bow even if it is onlyslight. That's a No Brainer!
I know guys that shoot a loop and still miss deer and/or make bad shots. Would they be worse without a loop? I doubt it[8D]
Jason, I would be careful putting that many years on a bowstring. I have seenagedstrings completely blow without even a little warning. To me it would not be worth the risk to put more than 2 years on a string.

Dan