Fermometer on Plastic?

I'm wondering if I should even worry about putting a Fermometer on my Better-Bottle and/or primary bucket? I'll be doing secondary in the better-bottle and I don't think temp is as important as it is in the primary. I'll only be doing ales for the time being (no lagering). I know plastic is a poor conductor, unlike a glass carboy.

thoughts?

As long as the ambient temperature in whatever room your keeping it in is in the yeasts preferred temp range and doesn't fluctuate wildly I wouldn't worry about it. Although, it is interesting to see how much fermentation can increase the temperature of your wort from the time you pitch until it's really active.

I have them on all my primarys and secondarys and rarely look at them.
Ales are done at room temps (in my case around 62f ambient) and lagers are temp controlled in my lager fridge.

THREAD RESURRECTION - you can use a fermemeter on plastic. Compared to glass the only real diff. is that it prolly takes a little bit longer to display change in temperature, like when fermentation is first starting and the wort starts heating up. But this delay isn't significant enough to warrant not using them on plastic. And it will show you the temp of your wort well enough for fermenting purposes.

The biggest issue with this is when the ambient temp is drastically diff. than the wort temp. I usually don't trust them if a change in temp is suspected, like taking a lager out for a D-rest. I wouldn't trust the temp. on the fermometer until it has equilibrated for a couple hours.

Fermometers FTW