To answer you question, I decided on the wally world Everstart 29DC Some might argue that it's not the best but several factors played into this. First let me say that if I used a TM as my main source of powder then I would have bought either an Interstate or Deka.
The Everstart has a 2 year replacement warranty, this battery is 860MCA and 100 Amp Hours, slightly more than the Interstate (on paper). I have a relative that works at WM (employee discount) so I got is for quite a bit less $$. I have a starting battery that I could use in a pinch in an emergency. Finally it's replacing an Everstart 27DC that has been of good service. I decided to buy this battery, which I did last night. Hooked it up to a charger and let it charge overnight. This morning it measures 13.8 volts, the only thing I have to do is run a load test which I'm doing later today. If all is well I will keep the battery, if not I will return it.
I understand that the Everstart is not the same quality of Interstate or Deka. I have noticed, and this is not a criticism of anyone, that opinions vary regarding batteries and for that matter trolling motors. My boat is 16'4", a 50 HP outboard, I carry 12 gallons of gasoline, two batteries and a boatload of fishing tackle.
My TM is a Minn Kota All-Terrain which has 40 pounds thrust, 12 volts. The All-terrain is the same as the Edge except it is uglier. It has 5 speed settings, I use the 2nd or 3rd and that pulls my boat fast enough. I have never used the highest setting 5. I figure replacing a 27DC with a 29DC will give me an added operating range but I have never (except yesterday of course) run my old battery down past 60% on a fishing trip. I have a fishing buddy that sneers at my baby 40 pounds of thrust and 12 volt system but it works fine and upgrading to 24 volts and more thrust doesn't make any economic sense to me right now. I did replace the bottom cover of the TM head last spring. A friends father is an Minn-Kota repairmen and he basically gave me the part. I had to completely disassemble the head so I adjusted it and lubed it and it really is a smooth steering TM now. I would rather put the hundreds of dollars it would cost to upgrade my TM into a side scan sonar. Another discussion for another day, but I have two sonars, both are lowrance with hybred downscan and I really haven't learned how to use everything they have to offer either.
For a battery charger I use a 10 amp trickle charger that was my Dads. When we were kids, money was very tight at times and my Dad bought it at a time when we had no money. I remember even my Mom bragging about this charger having a 50 AMP boost. This charger is at least 45 years old. About 2 weeks ago I took it apart and fixed the lead cord that goes from the transformer output to the battery. This is basically zip cord and the insulation was starting to dry rot from age. So I cannot recommend a battery charger but it's good to see that another poster has.
I'm thinking about getting a 2 bank battery charger/conditioner for the boat. It's a real pain for me to hook up the charger because I keep my boat covered with a canvas cover. But for now it works. But I'm just rambling here and not being of any help to you.
Pete, keep us updated, let me say that if I had the opportunity to buy what you did I would have purchased it as we have a bunch of HP restricted and/or electric only lakes and I think your boat would be great for them. My Dad has been gone for 15 years and I would give just about anything to go on a fishing trip with him now. We had so many good times on the water when I was a kid. Good luck with your boat!