I've owned 4 metal risered ILF/DAS setups and they all were nice with some differences. 17 & 21 Dalaa, I like my ILF 21" Dalaa for target work with lighter limbs. I like the extra low grip of the 4 they offer. The 17 Dalaa was fine but I like the 21" better. The 15" SKY TDX has the best feeling grip I've owned and it is the lightest and best balanced set up, and with Dryad epic LB limbs is the bow I use hunting. The other riser was a 19" TAC firefly, good riser built like a tank second best grip, easiet to quiet, high preload, but it's not made anymore.
If I had to pick best all around of the 4 it would be the 21" Dalaa, it is built very well and it does all things well.#2- 15" Sky TDX. #3- 19" TAC firefly. #4 17" Dalaa. #1-3 all close.
Do the more expensive limbs matter, in my limited experience I've found they do, smoother, more speed, more forgiving, just to list a few. It is again an individual choice if those things in a limb warrant a doubling of the price.