If you are going to use an abu in the surf, just be sure to do a real good job cleaning it. They are very good casting reels, but a little sand and they make a god-aweful sound and you loose that castability. I havent heard of any way to modify the drags, but for fish under thirty pounds it ought to hold up fine. I have used some of mine to land a 90# tarpon, and have caught two sharks over 100#s. I have had to replace the pawl, and the nylon gear the worm rides on in one. The drags always skip so have not reoplaced it. But for making long casts, I would use it over the spinning reels. (Just not enough beef for fighting big fish.)
I used my penn 535 last week to catch a 100# plus tarpon. It was very solid, and the drag held up for over two hours, the last fifteen minutes left alot to be desired however. I doubt you would get as good a distance on the cast as you would an abu, but its worth a look into. They are considerably more expensive, but I have destroyed three abus in the last two years. What ever you do, use your hands to apply additional drag and you will be able to compensate for a mediocure drag.