Smarty wrote:
Is there such a thing as a true "instant start" CFL which produces full
intensity brightness as soon as it is turned on?

I have some. They come on immediately, turn off, on, off, and then
finally stay on. They're first generation Philips CFLs with a
permanent 60 Hz ballast in the base and replacable fluorescent tube.
Heavy, too -- some floor lamps can't be trusted to stand up with one
installed.

As for modern CFLs, I don't know what brands or models are instant-on,
but I know they exist because some of them have circuit boards
designed for a thermistor (temperature sensitive resistor), but the
thermistor is left out (Max-lite, both original large base and newer
small base models).