The 7 footer is definitely a different animal. Renner action, maple rim, etc. The "knock" on the piano is that it may lack power for some people...however....check out the hammers and the shanks...I don't think it would take a lot of money to fix that "problem" relative to the piano you get.
But back to Petrofs.....very nice piano, very musical. Differs from Estonia in basic tone, and the Estonia may be possessed of better initial build quality. If you are looking at Petrof, do try an Estonia. The sleeper, though, may be Vogel.
Offered through Schimmel, it's an Eastern European piano with a bit of a German touch. Definitely worth a try...