Iv had the Razer Deathadder 3.5G (died in a failed mod attempt) and currently use the 2013 edition.
There isn't too much difference between them, the 3.5G has smooth plastic finish, while the 2013 has a rougher (but still smooth) texture on it. There is also a grippy rubber where your thumb goes, while on the 3.5G its just smooth plastic. The higher DPI is pointless IMO, 6400dpi is way too high to be useful, I have stuck with 1600dpi on both mice and notice no difference.
Also its Green rather than Blue (which was why mine died, tried to change it too red
).
The Deathadders are the best mice I'v ever used. IMO either one will serve you well, you just might have a preference either way depending on whether you like the rougher texture on the 2013 edition.
No idea on the Inferno, havent used or really looked into it.