I use cayston and tobi. Three weeks of tobi and 4 weeks of cayston. I use to do tobi for a month, casyton for a month, but that last week of tobi i feel crappy. I used colisitin a couple of years about but i think it stopped working for me or stopped working as good as it use too.
On a note of resistant, i know everyone is different, but my germs say i'm resistant to tobramycin but for some reason it always works. I'm 29 years old and have used tobramycin in all my "tune up sessions" for the last 13 years, every 6 months.