Worked wonders for me. I can sleep much better now. Previously I'd keep on getting up in the middle of the night due to blocked breathing. I, however, thought I'd be able to breathe through both nostrils at the same time, all the time but it is not the case. One of your nostrils would still be partially blocked most of the time. You would however feel a lot more intake of oxygen through both nostrils, just not at the same time. Getting a better sleep also helped me being more active in the morning and that feeling of tiredness during the day is gone.
Costs depend upon your location, I am sure it's different everywhere so you need to check with a hospital. As for how painful the surgery is, it isn't that painful at all, just very uncomfortable for a few days and it gets better with time. You'd be perfectly fine within 2 weeks, though the full recovery I'd say takes a month or more. Also, do remember there is a very little risk of losing your sense of taste and smell forever. It is I believe extremely rare but it happened with one of the sherdoggers, there is a thread, you'd have to search for it. Overall, I'd say it's definitely worth it and my quality of life has improved tremendously after the surgery.