Of course it's hard to beat Arnold and Sharon Stone in the original.
It shouldn't be that hard to beat Arnold's "acting". Just sayin'.
Actually I'm okay with remakes of movies based on books, if they are not so much about rehashing the movie than about re-imagining the story. I quite liked the new "Time Machine" for example, although I had not heard a lot of good things about it.
Maybe the same could even be true for the Conan movie that came out a while ago which I've heard only bad things of. At least, the new actor isn't that obviously artificially pumped up with steroids and stuff.
That Total Recall trailer to me looks better than I think the original movie ever was. I know, looks can be deceiving.
As for Philip K. Dick, he's one of my favourite writers because he combined two of my hobbies, reading SciFi and thinking about the possibility of the paranormal. Parapsychological elements are to be found in a lot of his works.
And he was a prophet indeed. I've recently read some astonishing things about his "exegesis":
Philip K. Dick - Exegesis
I guess you could write most of that off to his overactive imagination, mental problems, drugs, maybe a natural overdose of DMT or something, but he was also a very sharp observer and intellectual.
IMO, he would have quite liked Chris' trickster theory (look for the Zebra) or the holographic universe or even the conscious universe theories for example. Which he obviously "precogged".