Seriously,  $2000 and u can't shoot fast flight?  Find another bowyer!  I am an engineer and will clearly state that I can build a riser that will hold up to ff strings with no working knowledge of how to build risers at this time.   As engineering design projects go a tough riser is not complex.   At $2000 that bow should have a lifetime warranty. The bowyers work might be gorgeous but is clearly not worth the price being asked if it cannot handle modern strings.

FWOW, I've been shooting BCY 8125 which I believe is very very low stretch and very high speed on all my bows, with the only exception being the oldies that I DIDN'T build.

I've got endless loop 8125 strings on several board bows form red oak, which have only hardwood tip overlays 1/4" thick. They range from 25#-55# and I've had no problems. One of them is a lumberyard takedown bow, the one shown in my 'misssion 'red oak' impossible' post which is all red oak, riser limbs and all. Uses cheap cabinet bolts and inserts to hold limbs on and draws 40#.

I have a dacron string on my 45# eastern red cedar selfbow but thats only cause the jerk who made the string wouldn't keep his thinking to himself and delivered me a dacron string even though I ordered 8125. I've shot it and tuned it with 8125 and had no problems. It has only ERC tip overlays.

P.S. The issue of arrow weight isn;t considered here yet but I would imagine that the lighter your arrows are (gpp) the more potential there is for damaging a bow using an ff type string.

I'm shooting always above 10gpp and usually 12-15gpp.

I've been building a few lam bows and still have a lot to learn about timing.  Right now a FF string has almost zero handshock on my latest bow but I can't get it as quiet as I like.  Dacron is super quiet, but shows more shock.

I wouldn't hesitate to shoot any bow with FF if it has phenolic in the tips or if the tips are built stout enough to take it.  Lots of older bows have tips without much depth.