Undersink water filter recommendation?

Anyone have experience with a good brand/model of an undersink water filter system? I have a GE one I installed where the faucet is leaking and a new faucet cartridge to fix it is going to cost about as much as a new one. I'm not a filter fanatic, I'd like a single filter system that is reliable and I can get parts for when the faucet starts to leak, and also, if possible, reasonably-priced replacement filters that are easily available.

The filter and the faucet are two different things. You can get inexpensive "drinking water faucets" almost everywhere, and the replacement part, when needed, is very reasonable. GE filters are available at all Home Depot stores and are about as reasonable as any, depending on WHAT you want the filter to process.