I use my R888's "year round".
Here in my part of the world, that means temps rarely below 32 degrees, I never drive in the rain and always trailer to the track.
If you will *ever* be driving in snow, or you will have consistent cold temps, I would
not use these tires.
If you're driving in rain, well, R888's will be pretty good when new but when the tread is gone, you are asking for trouble.
Here's some cold temp info.