Hi,
FTO means Flight Training organisation (CZ/FTO - Czech FTO)
(A) stands for Aeroplanes
the number 22 is just registration number of Sazena, each FTO has his own number, i.e. FTO-001 = F-AIR, 22 = FlyForFun , 25 AK Letnany etc.etc..
List of all FTOs in country is available here
Organizace pro výcvik létání FTO(A), Ú?ad pro civilní letectví
From my perspective, if money and distance are not problems, go for any school in Prague Letnany (LKLT) The advantage that this airport is one kilometer from military LKKB and all your flights will be through MCTR is valuable experience