When I started Cruising nearly 3 years ago, I bought a starting battery that I thought was deep cycle but it turns out that it isn't.
It's warranty was for just 3 years and I guess you get what you pay for. On the other hand, I have had excellent service from my 2 Trojan T105 golf cart batteries that I use for my house bank, so I decided to get 2 of them for my starting battery.
Considering I am in the middle of nowhere and it is an easy walk to budget marine, the $350 I paid for them wasn't so bad. I did consider the mastervolt lithium ion but because I primarily use slow charging solar panels to charge my batteries, there was no point. Of course it took me most of the day to install them.