a float test is a better way of checking condition of the battery, load test doesn't tell you anything about the individual cells, a float test will tell you the condition of all of the cells and if they are discharging correctly. they should be able to do that for you as well at the flaps.
here's every test you need to preform on your battery to make sure it's up to snuff.
Inspecting & testing a battery
if you decide to buy a hydrometer and start running the tests yourself.
How to Use a Battery Hydrometer | eHow.com
i also run deep cycle batteries for the reason above,(CREATIX'S post) they are much better at recovering for complete discharging then a normal starting batteries and tend to have longer/more hours of running, the way i see it is if you can find one (deep cycle) that has the same or higher CCA (cold cranking amps) as a starting battery but can recover from complete discharge more effectively why not get that one? deep cycles are also better for accessories such as cb's,fridges ect, they are most commonly used in marine or rv applications for that fact.
here's a break down of battery spec's i robbed from another site. use the rating system below as a go by and make a logical choice that will suit you. i as well like the oddessy and die hard battery brands.
4. CCA, CA, AH and RC. What are these all about? These are the standards that most battery companies use to rate the output and capacity of a battery.
Cold cranking amps (CCA) is a measurement of the number of amps a battery can deliver at 0 ° F for 30 seconds and not drop below 7.2 volts. So a high CCA battery rating is especially important in starting battery applications, and in cold weather.This measurement is not particularly important in Deep cycle batteries, though it is the most commonly 'known' battery measurement.
CA is cranking amps measured at 32 degrees F. This rating is also called marine cranking amps (MCA). Hot cranking amps (HCA) is seldom used any longer but is measured at 80 ° F.
Reserve Capacity (RC) is a very important rating. This is the number of minutes a fully charged battery at 80 ° F will discharge 25 amps until the battery drops below 10.5 volts.
An amp hour (AH) is a rating usually found on deep cycle batteries. If a battery is rated at 100 amp hours it should deliver 5 amps for 20 hours, 20 amps for 5 hours, etc.
i'd also like to note they say that the CCA isn't important on a deep cycle battery and that's becuase most aren't used as a starting battery , but i do use them as starting batteries , so the CCA on a deep cycle is important to me, lol