Jeremy,

I agonized over the same question. I decided to go with the gutter mounts,
because I was similarly squeamish about drilling into the fiberglass, very
dubious about the ability of the fiberglass to withstand the forces
generated by the wind resistance vs. 2 sea kayaks (or multiple whitewater
boats) at 65 mph, and in general preferring to keep my van as close
to "original" as possible. Not to mention the fact that going with gutter
mounts allows you to change the rack spacing at will.

Nonetheless, if you look at various westy picture sites you will see that
numerous people have added the "fake" rain gutters seemingly without
incident. These buses are tough!

I went with the Thule 953 Super High Foot Gutter mount. These are MUCH
better than the Yakima HiRise adapters, one piece, 11" high. All the
clearance you need. If you prefer the cute Yakima accessories, the salesguy
at REI told me that Yakima now makes their accessories fit Thule square
bars as well. Best of both worlds.

My setup has served me well, without incident. The rack manufacturers
minimize the recommended uses to limit liability, as they assume
(correctly) that people will exceed those limits the same way they drive 15
mph over the speed limit.

Take heart. It's not a big deal to put the racks on and off. A couple of
minutes at most. It's more of a challenge to get the boats up and down!! I
now carry one one of those low-profile 3' folding stepladders from
Target/Walmart/HomeDespot...

Chris