Verizon should be releasing a Droid X case/window mount bundle soon. Thats the one I suggest because you don't have to take off the case to put the DX in the window mount.
Heres the mount without the case (Just to give you an idea):
Tried both the black silicone and BG and returned them. I liked the silicone but I was worried about it stretching. I just couldn't get used to the feel of the BG.
I'm gonna try the RF tomorrow and see how I like that.
EDIT: I got the RF two hours ago and like it better than the silicone and BG so far. It feels better than the BG but not quite as good as the black silicone. The design is much better than the BG and is slim enough to compliment the phone's design. I think this one's a keeper for now.
I got the shell/holster combo for my DX,I wanted a clip on. I liked the one with the kickstand vzw had to but it did not have the clip on it .I used my 25.00 coupon vzw sent me so it just cost me 7 dollars and some change.
Wait for the Seidio combo case / belt clip holster. My friend has it for her EVO and it is VERY nice. Everything else out there in the stores is sub par IMO.
I got the black leather snap on case w/ kickstand. Feels nice in the hand, allows for easier viewing of media, still a little paranoid ab just throwing it in my pocket (had a storm 1 and all the dust under the screen issues >.<).