I have this same engine and discussed the issue with one of FIAT's top engine designers (a really lovely guy, name of Massimo), earlier this year. While the original 999cc FIRE engine in the Uno and old Panda was non-interference, the 1,242cc version is not. So valves could meet pistons. I’ve never heard of this happening, nor of the belts breaking prematurely on this hugely well developed engine. So, if it were mine, (and mine is mine), I'd leave it another year.