the pros of these hubs are the safety for skid, in first places, cauz i've seen too many cheap hubs on fixie bikes out there ruining the threads and loosing transmission/brakes.
then there's the sturdiness and durability on rough roads.

obviously this is not aplicable in velodrome. I've seen many racers without lockring, in velodrome, to change gear faster. is this something you'd do out there on the roads? don't think so. =)

velodrome and roads are two different places. my idea is that what's the best in one, could be not that good in the other.
and if you really race, you won't use your racing wheels with superlight tubulars on the road, so you'll have 2 sets (minimum).

moser did the hour record with a 15t at the back.
i don't know you, but for me, 15t is more than enough. obviously what matter is the ratio. and you have to say what you have on the front. i have a 53t
=)