I recently had the same conundrum. I went no mips for three reasons…
1) they cost more!
2) i couldn’t work out whether a minor otb would be enough to make the inner mips membrane slip and thus ruin the helmet.
3) i read something on the internet that pointed out that even a well fitted helmet would slip on your hair and and move with your scalp to such a degree that the mips system is a little redundant. Give it a go…
Supposedly the safest sort of helmet is all smooth and roumd like a motorcycle lid so nothin can catch it as you scrape along the pavement and thus twist your melon (man).
So I’m probably wrong (and I’m sure this will be pointed out to me fairly soon) but i decided not to mips on this occasion.
Hope that helps!