Well Martin, I can't say that I agree with you,

1. When you install 2 or more of these switch's together the power handling drops by 200 watts. ( I am unclear if you have 3 switch's together whether the center switch drops by 200 or 400 watts.

2. As far as I could find out the only difference with the 1000 watt switch's is a larger triac which will not run any cooler, only last longer

Perhaps Larry Fine can shed some more light on this as he certainly seems to have the most knowledge on these kinds on things.