First off, I am not talking about the molded "normal" conversion top... I'm talking about the big camper top that extends the roof by 27". like on this ice-cream astro:

With some work, you could add windows and a roof rack to get this look:

so far my pro's for going high top are:
About 5-6 grand cheaper than the pop top
I could install it myself
interior head room would be awesome

i could store my surfboards inside stashed up in the high top on long drives, giving me peace of mind
can keep a "stealthier" profile when camping, as I could sleep in the upper level without popping a top
Cons:
Wind resistance will suck
Gas mileage drop
Low Bridges (a concern for me living in NYC)
It no longer will look like a mom mobile (chance of me getting stopped @ a bridge or tunnel toll booth go up)
I found the company that makes those tops and it seems like a good deal. Would be about 1000 dollars, then i would get the top painted (should be less than 300 at a friends shop) add windows (about 350 in parts) and install it (i can do that myself, all parts included with top). So for about 1600 i can do the big roof with windows.
Anyone else have any advice or opinions?