If it sounds good I'd leave it alone and play it, you might do the mods and find that you liked it better stock.
The SF DR's I've played usually have more clean headroom than at BF DR , which is not a bad thing IMO.
Here is some free info if you do want to try some mods
http://acruhl.freeshell.org/mga/main/sf_bf_mod.html
http://blueguitar.org/schems.htm