I am a complete convert to Tubeless, and have 4 sets of wheels setup.
But the experience I have had with a WTB i19 would put new users off, the wheels came with tubes but tubeless ready, so I took the tubes out, the tyres WTB Exposure 30mm with tan walls looked good but were very porous, I sent some pics to WTB saying they were not fit for purpose, they sent me some replacements (not tan wall) very quickly, I ran these until the tread started to delaminate (nothing to do with them being tubeless) but I always had trouble getting the front wheel to hold pressure over time.
I replaced these with some Panaracer Semi Slicks, (I liked the ride and feel of the WTB but the quality concerned me} still the same problem with the front not holding pressure, it was OK for a ride but would be flat in a couple of days.
On investigation there was air coming out of the spoke holes and nipples, so the valve was tightened, still going down, so tape removed, wheel cleaned, re-taped, still the same, so the conclusion was it must be something to do with the rim joint, but the tape covers that, anyway wheel left inflated so the fluid over is the joint area flipped to the other side for the next night.
It is still holding pressure, but I am not convinced it was the joint, its strange it is just this one rim, I have smoothed down the valve hole and the tape is sound round it, I will see out it goes.
I can see how all this would put people of.
Was it worth all the faff ? absolutely, I did 50 mile yesterday on 38mm Schwalbe G One Allround @ 40psi (they measure 40mm on the rim) mostly road with a bit off, average 16 mph, the comfort was fantastic.