+1 for all of the above...Having the mirrors in the "traditional" American location, under the vent windows, drove me batty. I felt like I was taking my eyes too far off the road just to see behind me. (If I'm gonna have to stare at my elbow I may as well just turn my head, right??)
I ditched my door windows at the first opportunity, and got the Lucas-style wing mounts instead. No blind spots, great visibility, and you don't have to take your eyes off the road and re-focus. Yeah, it gets in the way a little when you're bodging with a spanner under the bonnet,<span style="color: #FF0000"><span style="font-weight: bold"><span style="font-size: 12pt">*</span></span></span> but it's easy enough to work around once you're used to it.
<span style="color: #FF0000"><span style="font-weight: bold"><span style="font-size: 12pt">*</span></span></span> (I've been waiting a long time to use that phrase in a sentence.)