Good Evening, Piotr,
Sorry I can't help with the Xtol, but I've had very good result with Fomapan 200 and HC-110B. Five minutes is a good starting point. So far, after about half a dozen rolls, I have a good impression of Fomapan 200. Its box rating seems about right, and it has a very normal tonality, both outdoors and with flash.
I've noted three drawbacks, none of them of any great import: 1)the film base is very thin and slightly tricky to get centered and anchored in a SS reel; 2)the film is very resistant to puncture, and getting a film clip through it takes more effort than with most other films, and 3)it dries with a bit of a curl and needs a little time reverse-curled in a film reel after it's dry.
Considering that I paid only around $1.00/roll for it at J and C, Fomapan has been a good bargain. Good luck with your Xtol attempts.
Konical