They're definitely nice for hot weather! My KSC 35 can still handle that though.
Under normal temperatures the MA900 aren't necessarily more comfy for ME as Im a little conscious of the pads and tend to micro adjust them too often. They both less intrusive and more obtrusive so it sort of cancels itself out.
If I didn't already have the Anniversaries and X1s I could probably justify keeping them - but I DO have them.