My pool is also fairly stable, and I've wondered a if the kit is worth the $. Should I have not bought the larger kit, measuring pH and Cl, and leave the rest to the pool store.

Thanks to this site, I've obtained self confidence and understanding of the pool chemistry, that I would not have if I didn't regularly test for CYA, Ca, and TA.

That being said, to quote one of the moderators "stay ahead of your pool". I wouldn't be able to if I didn't regularly test. And I'm lazy enough that I would only go to the pool store in reaction to problems.