Thank you for the replies!
I haven't bought this machine yet, I went to look at it first.
I think it could be tricky to get the machine adjusted, so that it won't mark the leather. Also the roller is so big, that I will most likely have trouble to get it sew along the edge of my 1cm wide straps...? As the wheel is so wide, it easily drops off the thinner material's edge.
But it is a really nice machine, I'd love to get it anyway, just don't have room for two machines *G*.
It doesn't appear to be a corner stitcher, it looks just as the other 45Ks I've seen in pics, the corner stitcher looks very different.
I am leaning towards a proper triple feed machine, maybe Typical GCS6-7 if it works well, I will try that tomorrow, hopefully. Now I've tested a year-old Sewmac triple feed and it works really nice, it's just out of my budget.