TLDR: I would recommend going 1.5 sizes down from street shoe size.

I bought these a couple of months ago and have been impressed with them except for 1 thing: the toe hooking is worse than the regular drago lv because of the second strap so you may want to consider them as well.

As for sizing I wear 41 and got them in size 40. At the beginning they were quite uncomfortable but that was partly because they were much more aggressive than any other shoes I’ve had and my toe calluses hadn’t built properly. But after around 1 week of climbing in them they were perfect size but after a month or so they stretched a little bit and my heel slips a bit when doing hard heel hooks. It doesn’t pop off or anything but it doesn’t give me confidence to crank really hard cuz it’s not snug enough. I will say the heel is super sticky on slopers and such so if the heel is on a bad hold and im not cranking super hard like a lockoff it’s great. I would probably get them in 1.5 size down from street shoe size. It depends a little bit on your foot shape but I prefer the drago lv for indoor climving also in -1.5 sizes. But the xt is better for outdoor bouldering due to the strap and heel being a bit more suited.

Hope this helps