Did the specs for the Socket Rockets change? The LM15A pdf says "2. Screw an incandescent light bulb (up to 150W) into the LM15A. Do NOT use with fluorescent lamps!"
Do others have specific experience using the LM15A with CFLs?
No the specs did not change.
The Socket Rocket uses a triac, electronic switch, to supply current to the bulb. All triacs, even when gated "full on" (no dimming) add a small amount of distortion to the AC wave form when they turn ON at each AC half cycle. Incandescent bulbs could give a rip about any distortion.
However some CFLs and LED bulbs may not like this distortion, so X10, IMHO, does a liability CYB and states only usable with incandescent bulbs. So you use a Socket Rocket CFL combination
at your own risk. But I use Socket Rockets with CFLs (GE brand) and even wall wart switching power supplies with out consequence. However I did have consequence when I used Socket Rockets to drive transformer based wall warts (it took a year, but the cases melted because the small distortion made the transformer run hotter than normal).
Experiment using the CFL in a Socket Rocket. Check the bulb after a few hours of operation for excessive heat or smell. I have no problems with GE 23W and 13W CFL bulbs. Like Bill said "your mileage may vary".
Also, I had difficulty programming the HCUC in a Socket Rocket with a CFL bulb installed. Worked fine after I subbed a 60W incandescent for programming, then switched to the CFL. Since the SR has both hot and neutral in the light socket I can't explain why I had problems programming, but I ran into this more than once.