Here my .02 cents:
I had remote start on my 89 300E
I currently have remote start on my 95 E420
I currently have remote start on my 94 E500
All of my cars where taken to a different shop to install the car alarm with remote start. Not because I wasn't happy with one shop, but because it was a convience thing . I went to a local shop by my house and then the other times I went to a shop by my job. And one time I wanted a special two-paging alarm and only 1 shop in my are sold and installed it.
All 3 cars never had a problem with the remote start or any other eletrical gremlin (knock on wood).
i personally would worry problems with remote start. Just go to a shop that is insured and it is all good.