It seems hard to GM, with the 3.5 edition D&D mentality of EVERYTHING HAS RULES the RP-ness and DM fiat is hard to accommodate. Also distancing and actually running the game is difficult. I recommend a SARNFU system (squeezed, adjacent, reach, near, far, unreachable) So melee range is adjacent for a sword, but reach for a spear, pistol etc, near is close firefight, far is further (lol) and unreachable is you can see it but not hit it (as in it's too far away to accurately target)