the "cap" is 7 but belfs have an 2% spell miss chance against them, and nelfs and tauren have a 2% nature miss against them, therefore i usually run about with 6% hit which is just over 11 rating i believe (10rating= 5.95% i think if i remember right)
it depends on your class and what you're doing, youre a warlock right? therefore i'd advise you to go for the full 6%, especially if you're ally since UD have 2% extra miss from shadow spells so i'd pick SoJ and sunderseer.
In arena i'd use the full 6% hit regardless of your faction but for horde 4% is fine in WSG.
best way to get full 6% would be cape ring and SoJ =12rating, taking this will fully cap you and your other stats wont get gimped by this since cape is BiS anyway (well theres wsg cape...shh its just 1 sp), ring is debatably BiS since you'll need some mana and 7 or 8 int isnt too much to throw away for 6 hit and resi as a lock
edit; wrong %'s 10 hitrating =5.95%