The front light does draw 1.32 amps in order to get past the 600 lumens mark out of the LED. At that power consumption, there will be fair amount of heat for the small package. There is slot in the housing for heat transfer. I seen this on their S12 light and the Bikeray Speed II.

I had the chance to do a temp test. I ran a 12v mini fan blowing at around 5 mph or so. I have a mini digital wind meter to confirm my air speed. I took an IR temp gun pointed right at the front light and did a 10 minute runtest. The temp got up to 110 F in the first run and then 108 in the second trial. It was stable at those temp with no more case temperature rising. I did another test with the fan farther away and the case temperature went up to 120F.

I did not do a temp test without any air blowing on it, but I can imagine it will rise fairly quickly. I do not know how hot it will get if one were to use it on a hot sunny day on High mode during the daytime and had to wait a very long time at a busy intersection with no air flow. Leaving it on strobe should be no issue.