Well I'd say your amp would last longer than a Deluxe Reverb RI and probably sound better than a Dr Z (I've owned a few and played many). There are a few things in that schematic which make me guess that your amp would sound like a small BF Fender but be more focussed - ie not have too boomy a low end - and more mids on tap (the decent size Mids pot) and therefore it would most likely be a pretty good all-round amp. If the builder has his grounding sorted and good transformers then it should be an amp to last you for a long time.
One day I would like to visit Krakow and Warsaw. I have already visited the Czech Republic, Croatia and Slovenia, so only a few dozen more Eastern European countries to go! We have a lot of Poles and Croatians living here so at least I know how to order a piva or two.