My case is 40x56x25cm and it fits in short haul bins. Admittedly without spare space, but it definitely does fit. Therefore even with an absolute max size of 45cm width, that'll fit as the width just utilises more, erm, width, in the overhead bins. The 56cm depth and 25cm height are key to fitting in the bin. And no, that max size won't be out of order, relative to others' baggage. I hope this helps!

From vague memory it also fits into E190s but sideways, so maybe a bit annoying in terms of space it takes up. Others can probably comment on this better than me.