Can't imagine a Focotar being poor anywhere! Mine was excellent, but I replaced it with an El-Nikkor 2.8, much easier to focus. The 1C is a great enlarger to use (I also have a V35) but I found that I had to use the anti-Newton ring filter over the condenser. I also have the truly excellent Ilford Multigrade head on mine, and this makes it much nicer to use than the V35. Lately I have fitted the 1C with a 63mm El-Nikkor which is great for doing full frame prints on 10x8 paper, you do need an extension tube for this though.
When I had the standard head on mine (it was round and grey) you could use multigrade filters in a drawer above the condenser, was a bit fiddly though, and you couldn't split grade because the drawer was a bit tight and the enlarger would move a bit.