Was on the fence about Isofrane straps ever since they started again a couple of years ago. Just couldn't justify the $100 for a rubber strap.
Well, bit the bullet and got one for my sumo......it is a great strap, super comfortable, can't stop looking at it, well made. Is it worth the cost....yes.
My experience with straps is nato, zulu, di modell chronissimo, marine master rubber, zeiko oem rubber, italian rubber, oem sumo bracelet, etc. The isofrane beats them all hands down for comfort.
If you are on the fence,,jump over it and get the Isofrane, you won't be disappointed.