Stan's since... 2014... when Stan himself set up my bike for tubeless at Wyndham for the Citizens DH.
For valves, I generally use whatever came with the wheels. I pretty much always add sealant through the valve after the tire has been seated on the rim, so a valve with a removable core is a must. That said, I do really like that Muc-Off valve with the ball valve instead of a core. I see a lot of folks pour sealant into the tire prior to getting it completely on the rim, but that has invariably turned into a mess of sealant everywhere when I've tried to do it that way. So I stick with what works for me.