For It's expensive & the 2nd (necessary) fob is ugly as sin (looks like a 1970's remote control for a toy car-racing set, with a huge antennae! This was installed by the dealer, after showing me a fob that looked identical to the fob that came with the 2017. Then the bait and switch after it was too late! Horrible as I told them I did NOT want that ugly-ass thing!).
Read a few threads on remote starters, always surprises me how different the dealer installed systems are.
I'm not sure my fob is identical to other non remote starter enabled car fobs, but it looks normal to me. No weirdness or ugliness. Just the regular size and buttons.
And the differences on car shut off. Some when doors opened, some shut off if you dont press start button before engaging gear. Mine, stays on, i get in, throw into gear and I'm off. I was worried that I had a defect, but tried the process without fob in car and it does shut down when shifting in that case, so theft not an issue.
But I do feel the few min warm up helps, if it means 5 min into my drive I get heat as opposed to 10 or 15, I'm happy. And I suspect i get that improvement.
Course, other manufacturers give you toasty warm seats simply from a 5 min remote start, but such is life I guess.