None, man.
L5's in sealed boxes are OK, just OK.
But you can ask anyone here about how loud ported L5's, and L7's get, they're downright LOUUUUUD.
Even people on here who bash kicker subs, and say the SQ isn't very good, will still admit they get loud as hell in a ported enclosure.
IMO, L7's and L5's are the apex of the of the loudness to $$ ratio. Any higher $$ and you're simply paying for the same loudness with increased SQ, or slightly better loudness at the expense of a LOT more SQ.
You're not getting the l5's to sound good, nobody does. Put them in a big ol' ported box, and your neighbors will hate you for ever.
I love sqiare kicker subs, i always have, it's that attachment you get to the first badass system you had, and what everybody loved when you were growing up, if you can relate. But if anyone, ANYONE was ever thinking about getting L7's and putting them in a sealed box, in hopes of gaining SQ, i would send them in a different direction immediately. I would rather have two 12" type-r's or type-x's in a ported box for SQL than L5's or L7's in a sealed box for SQL.
Bottom line, don't get the L5's unless you want them to be loud as hell, and put them in nothing but a ported box.