Just curious. Why can't these be used with a dimmer switch?
The variable power apparently burns out the transformer. As will a 3-way switch, as I found out, though I have seen 3-way compatible CFs at the store recently.
There is dimmable one they cost more a good place to look is 1000bulbs.com. Link.
http://www.1000bulbs.com/category.php?category=14
There is two types of CLF lamps all the larger ones are fluorescent but some of the lamps less than 6 watts or so are cold cathode tubes which will last 25,000 hour I just bought a few of the 5 watt ones and the light is OK.
I have a side by side setup with a 42 watt CFL and a 150 watt "reader" lamp and the 42 watt is not as bright as the reader maybe = to a 110 watt.
There is a term called CRI which is the color rendering index. This is basically how much color shift you will get with a light system. A halogen lamp is 100 CRI and the highest screw type is around 82 CRI so there will be some color shift.
The lamps also have a color temp. For consumers they use the terms warm white or full spectrum or day light. This generalization is not varying useful. The better lamps will tell you the real color temperature in deg Kelvin. This number will be in a range from 2700K to 6500K.
A MR16 reflector halogen is around 3000K and a standard China floor lamp with a halogen lamp is a little more yellow at 2800K, an incandescent is around 2600K. The 5000K lamp will be light blue in color and the 6500K is vary blue in color.
Many of the CFL are sold as “Daylight" lamps and will have around a 5500K color temp. This is way too blue for most people unless you want to mix the light with outside light.
It is hard to beat the light quality of a halogen lamp. I have lot of CFL lighting but it has been a struggle to get the light right.
First a 13 watt is not = to a 60 watt maybe a 40 watt. They make a 16 watt that is closer to a 60 watt.
All the CFL lamps will require a diffuser or frosted lamp shade to make better light. This will cost some light.
In the bathroom I have a three lamp fixture with two 16 watt 2700k lamps and one 3500K lamp in the middle. This is the only setup I have found to give acceptable light.
In other rooms I mix the light with one halogen and one CFL in the two light fixtures.
There is a 3100k lamp I still need to try. Right now all of the "warm white" or 2700K lamps are too yellow but the 3500K are too blue unless mixed with the halogen lights.