Soldato
I don't know a lot about suits i confess and going from my experience of Topman, their clothes in my eyes seem to last and fit me very well - i'm quite a slim build.
I'm probably slimmer and always found M&S fine. I'll admit I've never owned a Topman suit, but a combination of trying them on and other people's stories has prevented me from buying one.
I've recently inherited my dad's M&S suit from ~1980 (not been worn for 25 years), still in perfect condition! They probably don't make them as good as that anymore though