hello, I have an MX250 with a MX360 tank fitted, they are identical shape & size,
I have seen an MX250 fitted with the SC500 tank, again looks the same shape & size.
not sure about the 125 & 175 tanks, although they can look identical in photos , but I think they are the same shape but scaled down slightly in size.
some DT tanks are the same shape & size but with a locking fuel cap & different fuel tap.