I am using Aleph 2's. I do not think you will have a problem and I highly recommend these amps.
The owners manual says that the amp has an internal temperature protection of 160F (70C). The manual also says they will run about 25 degrees above the ambient temperature. So if the inside of your house is 90F, the amps should run about 115F. I do not have a way to measure the temperature, but my guess is thay run a little hotter than that.
I do not know why you think the protection circuit is around 90F, but that does match what my manual says. So I believe you have plenty of safety margin between their operating temperature and the protection circuit.
Happy listening.