have any of you attempted to use a type of Bounded Accuracy yet?

i have, and i feel like it's worked pretty well. my system is this:

every attack has a given accuracy of 75%. so any attack roll over 5 will hit the target. however, the type of armor worn by the target will determine if the attack is deflected/absorbed. cloth gives 0 additional protection, leather +1, hide +2, chain +3, scale +4, and plate +5 (i think i got those right, writing from memory). so if your PC is attacked and the enemy rolls a 7, hide would protect the PC. i'm calling this the Armor Bonus.

now, my rogue and ranger weren't too thrilled about this, so i made this change - you can use either your Armor Bonus OR your Dexterity Modifier as your defense bonus, capped at 5. so a roll of 6 through 10 against my rogue misses since he dodged the attack.

one more thing - i've made it so that at-will powers gain +0 on the roll, encounter powers gain +1, and dailies gain +2.

the result: a lot more successful hits, thus a much faster game speed. i know, i haven't addressed reflex or will, but perhaps just using those modifiers in the same way would work. your thoughts?

(i also make every hit deal max damage, and make something up when 1s and 20s get rolled. but that's another discussion.)