Why a square kicker ???
BTW, used is ok........ as long as it hasn't had the snot kicked out of it. If it has, even free is too much as the hassles of installed and then de-install plus your time just ain't worth it. You just end up having to replace the crap.
I may have some decent used stuff kicking around reasonably cheap. Drop me a PM.
Current : 2013 Mini Countryman JCW
Past: '88 E30 M3, '69 BMW 2002 Ti, 2000 328i, Audi A6 TT, BMW X5 3.0i , Audi A4, Mini Cooper Clubman S 1.8T