Vote for R-15 from here also. Predator has NM 4.5 lbs trigger, but at least I want something really different trigger for a Varmint rifle. You can put Jard trigger into R-15 and your rifle is practically not more expensive than Predator.

I do not prefer Predator-style risers, because they do not extend upper receiver rail at all. I would prefer something like this instead + good quality ring set : http://www.brownells.com/.aspx/pid=2..._15_SCOUT_RAIL

Just my 2 cents