I see no issue. Go experiment and report back your findings.
It worked, mostly. Ran out of time to bleed it properly before work but it definitely grabs. I ran into one very small hiccup actually, the part that the hose threads into at the caliper is a different diameter on the road caliper vs on the X0 Trail caliper. so I swapped that as well and so far so good. Can't wait to see how it grabs once the pads are worn in and the bleed is correct.
Podiums aren't very big though. I like mine but I doubt they're much bigger than the Saint's, although I can't find that info very easily for some reason.