Yes I was! A lot of the TTS holders I see from china don't have a ground mating surface; this one did, so I felt comfortable getting one. Not super cheap, but I'm from europe, so it's still better than importing it from america. I also got an ER20 holder from the same seller to test out, as well as some ER20 collets from different sellers to compare the runout.
I was looking at one of these: https://www.aliexpress.com/item/3283...3e2e4c4dv2gJgl
I'm a fool though; I bought the 80 mm 5T version not realising the arbor is 27 mm lol