It's funny ... 90mm seems to be one of those lenses you tell yourself you should own and use but never do! 😛
I have two in the cupboard which haven't seen daylight in a year now ... an f2 Summicron and a Tele Elmarit. I used the Summicron a couple of times and thought ... "Wow that's nice, I should use that more!" Never have though ... but I really like my 85mm Zuiko on my OM's and use it quite a lot! 😕