I do not remember seeing a lot of discussion about the FT03.
A quick look into the Silverstone Case Owners Club shows that only 7 members are using it:-
I personally am fond of the FT03's square and tall design/shape. And it is certainly in my consideration if I ever need a smaller case.
One limitation (and it is also its strength) is the bottom-intake-top-exhaust design. This is very well suited for graphics cards with ''front-centrifugal-intake-fan-and-rear-exhaust'' but is not well for any other types of cooling. This needs to be carefully considered when using this case, IMHO.