I recently got a Minolta 28mm ƒ/2.8 MD and a Minolta 28mm ƒ/2.5 MC for my XG-M. I haven't gotten any rolls developed yet of anything shot with either but I've been shooting both a lot. I have been wanting to try a 28mm since it's been years since I had one (and even then just the wide end of zooms!). I've been a 35/50mm shooter for years now but I've taken quite readily to the 28.
One issue with the ƒ/2.5 is the thorium glass turns yellow from radioactive decay. I set it in windowsills around the house for a few weeks and it's bleached some of the yellow out but it's still very yellow. The lowered contrast and single colored cast make it a bit harder to focus even with the XG-M's big, bright viewfinder. I want to give it more time this summer when we have fewer overcast days.
I'll share some scans here once I get some film developed.