Well with the led lighting in the new unit and having a generator and solar available, I believe I am going to bite the bullet and spend $350 for the GPL-31T or $420 for a GPL-31XT. The GPL-31XT has 125 amp hours. We have always been good with 2 standard group 29 or 30 batteries with a total of 200 amp hours and regular lighting. So that's my story and I am sticking to it. Any other input is welcome. I won't be making the purchase until late week, need a few xtra $$$.