I don't use the Neti pot, but the cheaper plastic bottle version. I think the bottle is probably easier to use. You just press the opening up to one nostril and squeeze and before you know it you got saline water going up into your sinuses and out your other nostril. If you're congested, coughing, sore throat....this thing kicks ass. I highly recommend it. You'll be breathing clear right away, for a while anyway. I use it on a regular basis. It's really not uncomfortable at all. Blowing my nose afterwards I usually get my ear canals to open up a but too.
Using plain water or salt water is not as safe as saline solution and could cause problems (from what I have read).
I think the bottle w/ 50 packets was about $14 at the drug store. I started using one when my doctor prescribed it for a cold I had. I've told lots of friends to get one. It is money well spent.