Why are they better than the A8N32 that I currently have?

Im interested to know as I would swap out if there was a decent advantage?

It would be housing an X2 4800+ and 2GB of GeIL RAM

You wouldnt gain enough to warrant it IMO.

The main difference is that it has a lot more BIOS options so you can fine tune a lot more than with the Abit to get every bit of performance out the system.  
I do use them in systems that arent OCed because they are very stable and I have had very few failures.

Of course if your where building a new system or replacing a failed board I would then recommend a DFI board  

Ive got an MSI and it gives me absolutly no overclocking options really,
I curse every day I use this mobo.