My CFL's have been in use for 8-10 years, so long that I still have some from a purchase at IKEA.
Sure a few burned out, about 10 in the entire house in the whole time, so I'm happy.
I recently replaced a few with LED's as I got those for $3 each.
I don't buy any of the 88 cent packs anymore, as I have about 20 bulbs left to use up, will probably move first.
I have a CFL inside a closet fixture, upside down, turned on/off 2-4 times per day for the entire 8 yrs, it's still going fine, but will probably replace it with a LED for the instant light feature.
The outdoor lights that are on from dusk to dawn are CFL's, they get dim in cold winters, but bad people are not out as its too cold

I'll probably replace those with LED's as they will stay bright in winter.
The outside ones that are on about 12 hrs per night are the ones that have burned out the most and they are upside down as well, probably have 1 or 2 per year burn out.
I'm happy with the CFL's, but will use them up and switch to LED's when they are cheap ($3 or less).