I don't know the terrain of the Jock, or how fit a rider you are...
but like most everyone else, I believe the rider is the most important component.
that said...let me say this...
most aero profile wheels like the shamal (38mm rim) weigh more than lower profile rims (open pro about 18mm) and are used primarily for flat time trial and road races where there is very little climbing and flat out speed is the goal and weight is not as much of an issue.
however if you're doing a ride where you have a 10 or 20 mile climb at 7% to 15% or greater, weight becomes an issue (at least to some of us). if you can lose 1/2 pound or more in wheel weight, rotational inertia and all that, you'll feel it over a 100 mile jaunt. i have everyday wheels for training, and lighter wheels for "special" occasions.
some carry the weight thing to the extreme...such as Lance using a downtube shifter for his front derailleur rather than an STI in last year's tdf. (saved 5 g or so)
if you can afford lighter wheels, and can justify them based on doing a lot of climbing, go for it. but if you only do small climbs infrequently, forget about it.