I have several different wattage units all from one manufacture and the power supply layout is basically the same from smallest to the largest. Its just a few capacitors, resistors, and coils that are different.
The actual circuit layout and schematics are the same. They just tweak them for slightly more or less power in reference to each other.
For my experience with CFL's the American made ones do fail a suspiciously short time after the warranties are up just like most American made stuff seems to now.
I have bought 4 packs of an American made brand and all four died in the same kitchen and bathroom fixtures within about one weeks time of each other in said fixtures. Once the first one went out all four where dead within a normal weeks use.
The Chinese ones I replaced them with one out of the 8 went out the first day and the other 7 are about 3 years old and used every day.
The Chinese ones either quit the first day or last for years. They dont seem to have much in between unless they are in too hot or too cold or harsh environment for their design.
Unfortunately thats also where so many CFL's regardless of manufacture die at. No one reads the box and finds the ones designed for their intended application.
They do make them in cold, hot, and harsh environment designs if you bother to go and look to find them. If it doesn't say specifically rated for XX degrees below zero or above XXX degrees its a generic middle range unit that will die right away when used in a place that too cold or too hot!