This string makes you think. I have the 18 v DeWalt tools and really like how they work, but my batteries are ageing and don't hold that much of a charge. And the 20 v is nice, but one strong 4 amp battery is about the cost of a pair of 18v. The impact driver is priceless and I'll probably keep it running as long as possible, but I ran across my old 1/4 inch corded drill the other day so when my DeWalts die, I might just use it and skip the cordless. I once had a Makita battery rebuilt, but it didn't really work properly.
Batteries are a real issue these days. I inherited a small (3lb) oxygen concentrator from my brother last year, and the batteries are about $500 each, and both batteries just won't take a charge after sitting around for a year. I just use it for sleeping when traveling, so I don't really need the batteries, but I'm thinking I won't be ponying up a $1,000 any time soon.
The more I do, the less I accomplish.