whats a good inexpensive solar charge controller?

[hpcbmw]

I'm going to have an 80 watt and two 15 watt solar panels on my 30' 5th wheel. The RV is boondocked and I only use it on weekends. I've got two 6v deep cycle batteries hooked up together to make one 12v battery ( I can't recall - is that called series or parallel?). Those batteries are getting kind of weak, so I might be replacing them with one 12v deep cycle battery if they don't hold a charge this summer.

What is a good charge controller? All I need is something that will charge the batteries when I'm away all week, without overcharging the batteries. I want something inexpensive, but safe and reliable, since the RV sits empty for weeks at a time.

I got the 80w panel with a used camper I bought, and the two 15w panels are part of a Harbor Freight 45w set. I'm using the third HF 15w panel to keep the single 12v battery maintained on my rarely used FWC.

Is this Sunforce 60031 10a controller a good buy at $33?
http://www.amazon.com/Sunforce-60031-Digital-Charge-Controller/dp/B001DZONCW/ref=sr_1_3?s=automotive&ie=UTF8&qid=1370317383&sr=1-3&keywords=solar+charge+controller


Thanks for any help!

 

[ntsqd]

Can't keep on the solar stuff (other than to suggest looking up the HandyBob blog and the refs to it here), but the way that I keep it straight is "Series" is one after the other and "parallel" is side by side. So series adds voltage without changing capacity and parallel adds capacity without changing voltage.