My li'l ol' SirSpider.com search site uses a few of my own terms plus backfill by searchfeed and ah-ha.com. I had also tried search sites with kanoodle and also with ah-ha by itself. Ah-ha was better than kanoodle, but I have found that by using the "SmartSearch.cgi" script I can promote my own terms for free and I make a few $$$ with a monthly check (yes, every month so far this year) from both SearchFeed and Ah-ha.
Once I get my 1500-2000 searches per day up to 10,000 or so, I may look again at feed alternatives. :-D