My old HT has coil U-Turn 80-130mm. The actual suspension travel never seems to be more than 100mm and it give just less than 10% sag. Around 100mm seems best compromise for general riding, but on steeper or rougher downhills, 130mm slackens things noticeably which helps make me brave!
The Giant FS has a light F120 which gives about 100mm of non-adjustable travel and I pressurise it to give 10% sag. Downhill I wish it was slacker, uphill I wish it was lower.
I had thought about putting the coil U-turn on the Giant to see what happens, but it’s about a kilo heavier than the F120!