Safe T alert 70-742-r

[tjvpga]

We are finally getting ready to take a trip after 1 1/2 years! Our CO detector needs to be replaced. Its the Safe t Alert 70-724-R. I understand this alarm has a built in solenoid relay that can shut down the propane supply. Is this alarm a good one? I have read different reviews that said it did not detect propane when it should have. Is this difficult to install? is there something out there that's better? We have little dogs that would get affected first and I want to be sure we take every precaution to prevent any disaster. Thanks!