200 lbs weight.
Not listed rider vs gear????
So maybe....
180 lb rider
20 lb gear
25 lb bike.

Currently: 68 spokes.
Now, you want to build a set of wheels with 50 spokes????

Save the weight of 18 spokes + nipples. Maybe 100 grams worth of spokes + nipples????

Again, it depends a bit on what he is currently running, but I'd rather the peace of mind to just stick with the 36/32 wheels... Or, perhaps something like 32/28.

The Mavic Open Pro is a bit old technology. Not as "aero" as some of the new wheels. But, it is also one of the last rims with full sockets/eyelets. I just wouldn't be so quick to discount them.

How many minutes will fancy new wheels shave off of a cross country ride?