I have had suspension or ridden bikes with suspension by, Pro Circuit, MB1, Factory Connection, Too Tech, N2Dirt, Stilwell, Race Tech WP in Murrieta, MX Tech and Pro Tune. I am on my third bike with XACT / AER suspension. I did the inset thing with Del Saggio in one them and yes, inserts are one of the best mods you can make, but in all honesty hard to justify for the price.
Right now I am on a '23 GasGas Factory Edition 450. After scouring the net and asking around, the least expensive for the best result came down to a revalve by Corey at ProTune or JB at JBI.
Protune wanted $120.00 and JBI charges $400.00. My plan was to give a revalve a shot, and if it didn't work out go with a Raven spring conversion from Jeremy at MX-Tech ($1,600.00)
I went with Corey because the price was right and he had done work for me before. ProTune is in Ohio and it may seem like a hassle to ship your forks, but it's actually super easy. You contact Corey, discuss what you want and he will email you a UPS link for a prepaid shipping label bar code. You go to UPS and they will print out the label and you are good to go. The best thing to ship your suspension in is a plastic foam lined rifle case that you can pick up at Walmart for around $30.00.
Because the WP XACT only has valving in one side, as long as your suspension is new or near new condition you only have to ship one side.
The stock valving on the new WP XACT is absolutely garbage. You have to run higher pressures around 150 to get it to ride in the top of the valving stroke and then it wants to dance and skip in small bumps and entering turns. When you drop the pressure (140's) to soften the forks you will get less skipping of the front wheel, but it dives into the turns and blows right into the mid stroke becoming harsh.
For $120,00 on the revalve I really didn't expect a lot, I really just hoped to make the bike rideable until I could scrape together the $1,600.00 for inserts... I got the fork back from Corey and his recomended settings were both clickers at 18 out, 145-149 lbs of pressure for a plusher type of Vet intermediate ride. First lap was a holy shiat lap! Huge difference and 100% in the right direction. Not a spring insert KYB type of ride, but night and day difference and all for the better. Super stoked and as I get a few more rides in I think I will just keep the revalve and forget about the inserts. It really is that good.