Any manufacturer is going to say that about a cold startup however if you consider the other side of the argument, they also say you shouldn't beat on it until it reaches operating temperature because it's bad for the seals. Personally I'd rather her let it get to operating temperature before she gets behind someone going slow as shit before the car warms up and punch the gas (it happens to us all).
That being said, if you do go with a remote start, go with the Viper brand, we've used it here at work 14 years and never had issues with Viper...just put one in my gf's car actually. Works wonders...now she drives everywhere