I have a Compaq laptop, about four years old, whose battery is starting to go sour. I like this unit and would like to keep it a while longer before I have to upgrade. A new battery will run about $125. However, I've some aftermarket units on eBay for about $75. I'm wondering if anyone has had any experience with non-OEM batteries and if they're a worthwhile replacement option. I bought an aftermarket power cord/supply and it has worked fine.