Oof, blast from the past, I remember that debacle. If only we had a new equivalent of MK's program from GT3, where we could easily load a replay in and see immediately if a car's to spec...
Considering how it literally took years to crack hybrids in GT4, chances are good they won't happen for a while in GT5. PD apparently caught on and don't like the practice, as that's the only way to explain why they went to a whole new system between GT3 and GT4. I do wonder about GT5 though, and even more, the weird fact that GT5 saves are a fraction of GT4 ones

.
alexleighton brings up a good point though; the ability to transfer garages could be handy to those who use their GTP_ account as their secondary. I'm lucky in the sense that's my primary GT-related PSN account (my main PSN account for all other games is my GT "secondary"), but surely having to transfer cars around as is needed currently must get tiring.