The answer to your first question is yes, mostly. The length of the horn and the fingerings are like a 3-valve F tuba (that is non-compensating), but...
It is a common problem for all baritones: the diameter of the smaller bore, compared to the euphonium, exacerbates the accumulation of condensation,...
On my Festivo, I've found that the 2nd valve is quite flat. I always have to play high A with 1-3. High G is problematic, 1-2 already is quite flat,...