One main thing which prompted me to switch was an eight-tube fluorescent fixture directly over the large desk in my office. It is very difficult to reach, as it is installed inside a secondary enclosure built into the ceiling which is an absolute B***h to access. It has been acting up for years and I was down to having only four of the eight tubes working - sometimes. I knew it was the ballasts and not the tubes themselves. As most ballasts run $20 each or more, and this particular arrangement required four ballasts, it was cheaper to change to LEDs and remove the ballasts rather than to replace them, to say nothing about eliminating the difficulty of changing fluorescent tubes in the future. Hopefully, I'll never have to worry about changing either tubes or ballasts in this fixture again. It took me most of Sunday afternoon to do that fixture. All of the other fixtures were much easier to work on, and it took me about an hour for each two-tube fixture. I also had a number of single-tube fixtures, which were even easier to modify. All told, I had a total of 26 tubes I replaced, with six remaining for the future.
You may find that LED tubes are much more expensive at Home Depot or Lowe's than what I paid on eBay. They are probably made in China (I am not sure where they were made), but are shipped from somewhere in the USA. It took only a couple of days to receive them.
From what I have read, the LED tubes take about half the electricity for equal light output and last at least 5X longer than fluorescent tubes. They are all T8s, smaller in diameter than conventional T12 fluorescent tubes. And they are transparent plastic, not glass. But they fit into any 4' fixture. Also available are 3' and 2' LED tubes.
"Costco sells fluorescent LED lights that you do not even need to remove the ballast. Just pop them in."
True, they are (or at least were) available, but I have read that there were problems with them, and in fact many were recalled because they quit working soon after installation. I checked that out before I began. For me, eliminating the ballasts altogether made more sense for reliability. For the eight tube fixture mentioned previously, it wouldn't have worked for me anyway. Every one of the four ballasts was dripping tar, as I found out when I got into the fixture.