Ok, I've been limping along with Frankenstein's bastard child cordless tool miasma for about 4 years now.
I finaly decided to bite the bullet and buy a new combo set. After much deliberation I decided on the newer style Milwaukee 18V XC lithium series.
http://www.cpomilwaukee.com/combo_kits/2691-24.html
I got a 4 piece: light, hammerdrill, sawzaw, circular saw w/ 2 batts and charger; bonus free impact driver tool only, and a mail in rebate for a free battery, total cost $550
I was really torn between this set and the Makita set because I already have a Makita Hdrill and impact w/ 2 batts and charger.
I bought the set a local True Value because this hardware store has a serious tool department, a huge rental and repair department, and records all your tool serial numbers in their computer when you purchase them and really goes to bat for you on warranty issues.
The head of the tool department sold me on the Milwaukees. He said they are built better, they stand behind their tools, and they are really going after the 18V cordless market and ramping up their offerings to compete w/ DeWalt and Makita.