I design and integrate back up power systems (UPS, Gens, etc; up to 10mW) as my profession so I deal with battery manufactures on a regular basis. There's one thing rarely known about battery companies... there are probably fewer than two dozen lead acid battery manufacturing facilities global and about only six in the US. Lead acid battery manufactures is the US are C&D, Enersys, GNB, Tojan, East Penn and Johnson Controls. As far as "the best quality name brands" for deep cycle I'd put my money on East Penn (Deka) or Trojan. The Optima line (by JCI) have a great technology but due to their technology they don't have a "true" deep cycle battery.
Deep cycle = fewer large plates
Starting = many smaller plates
Dual purpose = some hybrid form of starting and deep cycle (personally, I'd stay away from these for any application)
The batteries from Walmart are decent bang for the buck but I live in AZ and I've found them to be extremely sensitive to high heat conditions. But one way to look at it... you can buy 2-3 Everstarts for the price of one Deka or Trojan and about anywhere you're bound to be close to a Walmart. Walmart has a great return policy... I went three years with my boat battery (Everstart group 27) where I returned it five times no hassles for a replacement. End of it all... I just got tired of having to return the battery twice a year.
One other thing... if you are running parallel batteries, both batteries should be bought and replaced always at the same time. The is especially true for deep cycles.
JC