I have the same problem.. now choosing between these two.
But i did have the Ferrari GT Experience which is basicaly the same thing as the F430 except the force feed back and some cosmetic stuff like metal instead of plastic on the peddals and the rubber on the wheel (and also the shape).
I'm pretty sure, after i saw some video reviews, that under the hood they used the same plastic and buttons and all that as in the GT Experience.
The problem is that after two years the break peddal broke (beyond repair .. plastic snapped and one gear peddal stopped clicking but still worked, which is a bit anoying to press and not click).
I did not use the DFGT just saw it a few times in shop and handeled it a bit.
Ferrari Pro: good looking, nice quality materials, great peddals.
Ferrari Cons: breaks easy and from what i saw it's a bit more expensive than the DFGT.
DFGT Pro(from what i heard):better FFB, and last longer, also a nice gear stick.
DFGT Cons (from what i heard): poor peddals, and cheaper material quality.
For now I think i'll buy the Ferrari (looks better and the peddals are great) and save a bit of money over the course of the two years (which it will be in warranty in case it breaks) and buy a better Logitech once i've saved enough.I would have bought in a flash the DFGT but the peddals are just awful.