Ok I know there are some battery gurus on here.I fish electric only lakes so my deep cycle batteries are my main lover source.I run 2 24 volt motors on deep cycle acid batteries .I was wondering if agm batteries would  be a good upgrade for my needs and what are the advantages and disadvantages.also if they will last longer per charge etc.

I find them to be lighter weight and longer lasting than flooded cell batteries.  They can also hold a charge a lot longer than flooded cell batteries.

If your only power is battery then i would stick with lead acid.  They require more maint and are not as light but carry more charge than the same size of any other style.  There are always tradeoffs but if your only source of power is those batteries you bet i would be running lead acid 31's or larger.  If you have the big bucks then maybe the newer tech of LI might be better but thats out of my price range

Here's a good primer on the different battery types:

 

https://www.batterystuff.com/kb/articles/battery-articles/battery-basics.html

 

The cost/benefit analysis of flooded wet cell versus AGM is different for different people.

 

Like Angry John, I'd go with flooded wet cells, especially for the cranking battery, because: 1) They're much less expensive to buy; 2) I'm not concerned about the relative safety of flooded wet cells; 3) My batteries get used often, so I don't need AGM's advantage regarding storage length; and 4) I sometimes run them down below 50 percent, which reduces AGM's advantage regarding the number of cycles they can last.

 

My new boat came with Interstate Marine (green top) Group 27 flooded wet cell batteries. When fishing an eight-hour tourney with the livewell pumps running, the charge in my cranking battery gets so low that my fish finders reset when I start my outboard motor. I definitely need a larger cranking battery and plan to replace the 27 with a 31 when the 27 dies. Mercury recommends a cranking battery with at least 1,000 Cold Cranking Amps for my motor, which the current 27 does not supply.