I have one on XT20, also used it on my XT10, definitely worth having in the kit bag. I wanted to lessen the load in my camera bag and it certainly has done that, as above the aperture is a bit slow but I don't do "birding" etc in mid-winter so I am looking forward to using when the light gets a bit better. Nice and light and IS seems pretty good too, very unobtrusive noise wise, can hardly hear it, I thought it was broken by comparison to my Canon IS motors.
To my eternal shame I bought mine "grey" (I think) as it has resellers 2 year warranty.
UK camera store £208