+1!!   especially  when  considering the price!    I  really don't recall any  disconnect  for less than 80-90 bucks  on  recent searches!     

Early last spring  I had  a  tractor  suddenly  'burst'  into flames in the middle of the night...   a disconnect  would've been nice!

I   went with a single  31  on  one of my  massey  540  v-8's..    and  even  though  those tractors  were  wired  with 2 batts  in parallel,     it  was still   problematic    keeping  both  batts  'equal'..   either  from cable condition,  and/or  the batts  themselves.

Sure,    the  one batt   is limited  on  cranking @  zero degrees..  but     the   reliability  of  one short cable  almost makes up for it.