ILf limbs have so much money poured into R&D, custom bowyers could never afford it. The most easily tunable set up imaginable, and the most effiecent limbs, pound for pound are some of the TT Carbonwoods. I used to be a wood snob, now all my go to bows are metal ILF risers, and my old faithful Quinns. I believe the 19"-21" riser is the most forgiving, and the 17" a close third. Also, 2x what Bill and Longstick said above. The main con, is you can tinker yourself to death, and when continually changing, you never get your form for the bow down pat. I have a set of limbs that adjust up#4, so I start off shooting light, then increase # as I get closer to hunting season, that way, I work on my form, and shoot and hit better as a hunter.