up ?! are u shure. the 875 are much wider at the front then the gts, but they have the same length. so you have decide. Yep, I'm sure. I tried the 7.5's in the 875 and I could feel the front of the boot slightly with the tip of my toe (especially when the boots bend while walking). As this would drive me nuts, I opted to go with the 8. YMMV.