wet cell or agm battery
 

Which one is the best bang for the buck?Any drawbacks for either one?

It depends how you use the batteries so you need to provide additional info. As a starting battery I don't think they are worth the expense. As a house battery they may make sense.

thay will only run the stereo and nothing else.The starting batt is a regular starting batt.

But if you have an onboard charger, or if you use a single charger ever to charge both batteries you may want to be careful mixing. Usually best to stay with one type, and replace them together.

A word of caution, charging requirements for both batteries is different.

If you leave most of the 'high-tech' batteries discharged they are more likely to fail than conventional. It just requires more thought on keeping the right charge in them.

Went with interstate group 29 thay have 125 amp hr for $79.00 at sams seems like a good deal .

IMO AGM's aren't the way to go in a marine environment. Like has been stated before, they have different charging requirements than a conventional battery. If you charge them at anything over 15.5 volts they're toast. From what I've seen they are more prone to early failure, too. I usually see at least 5 years from standard automotive batteries, but am only seeing 3-4 years for AGM's.

I'm sure there are other opinions, and probably those that have done more specific research, but for my money a good standard deep cycle does the trick.

IMO the only advantage AGM or gel batteries have over wet is their mounting options. Some argue they are mroe durable ( vibration/shock). I just dont' see it. They are expensive for what most people use them for ( true deep cycle application)

Just the other day I was in the auto parts store and some guy was flying off the handle b/c he spent $250 on an optima yellow top and now its' dead after 9 months and they are having trouble witht he warranty. The sales guy said you shoudl have spent $50 on our house ( flooded) brand and we coudl hae replaced it for free up to 3 years, lol.