Depends on what you want to use it for. For around the house use, the Ryobi would be fine. I find that lack of use is killing more batteries than overuse. I have Milwaukee 18v Fuel tools for HVAC work and am still using original batteries and have bought used batteries, and still haven't lost a battery yet in over 4 years. I also have Makita and Hercules tools that work well too, but if you're going to work a tool hard, then go for the best.
See the pic below, I know it's hard to see but that is smoke (it actually had flames coming out, but we werent fast enough to get pics) coming out of that Ryobi drill. Once the magic smoke comes out, you can't put it back. Ryobi doesn't appear to have the best overheat protection as others, because even the Fuel drivers will kick out rather than burn up. I was using a 4" hole saw to drill through an 8" deep roof on a commercial job. I was going to go to the truck for my Milwaukee 18v drill, but the guy from the building said to go ahead and use his Ryobi, well, well we went through THREE of his Ryobis before he ran out of drills and I went to the truck and got my Milwaukee and finished the hole no sweat. That doesn't mean Ryobi is junk, it means they just aren't designed for extreme use/abuse. Just so you understand the guy went to a big box store and bought three (maybe more, I dunno) Ryobis on sale at Christmas for $99, and up until that point had a stash of batteries and drills. If used for reasonable jobs, the Ryobi would do you fine. I wouldn't be afraid to own one, and if you do go through a battery, they're usually cheaper.
I will say, if it were me, I'd buy one of the new subcompact drill/driver 12v kits for home use, like the Dewalt Xtreme or Makita CXT subcompact. Todays 12v stuff is as strong or stronger than the old 18v rools. I have a 12v Makita brushless subcompact drill and impact driver set and I gotta say, they are awesome. The 12v Fuel Milwaukee stuff is even stronger, but I find only a few times I need full 18v power, but when you do, nothing else will do.
Funny story..
I bought a new Fuel 18v hammer drill/driver to replace an older one and we were installing a system, where we had to move a dryer vent and my helper was drilling 4" holes through floor joists to move the vent. I warned him to use the aux handle on the drill as it was not the old drill and it could hurt him. Well, he didn't listen and I was outside when I heard a loud thump, whump and a yell. when I went in to see what happened, (as if I didn't know), and he had been up in the joist pocket and the drill kicked back and got him good, twisted his wrist and banged his head. So don't think for a minute these things aren't strong, you'll be unpleasantly surprised. Thank goodness no serious injury, but a wakeup call. That kind of power is only for some jobs.