Most of them should be pretty similar. Just make sure if your planning to do any extreme activity that it's covered. Guatemala isn't a big extreme sports place (at least wasn't when I was there) but I know a lot of people rent dirt bikes near lake atitlan. You may wish to read carefully your coverage if you plan to do that. A lot of plans will cover you if you have a motorcycle license back home which many may not and in a foreign country likely won't ask for it. Many policies cover scuba but only if you have your PADI
Look at things like exclusions for zip lining or other activities you may wish to do.
Have a good time and remember you'll need to go back to Guatemala City for proper hospitals so be careful on stuff liek bridge jumping and just general clumsiness. Unmarked Holes in sidewalks are common. unstable hand rails tripping on cobble stone