I ran warmers last season...As far as a spec tire such as Solaris I found it beneficial to run warmers when the track/ambient temp was cool outside....but as it became warmer, such as in July/Aug., the car would feel a littel "greasy" when I ran them.
If I were to run this weekend I would definately use them....I have also had great results running two or three hot laps to get the tires warm, just before a qual. again just as long as the asphalt was warm.