I have ridden close to the same two wheels you are speaking of: Kyserium SLs and Carbone SLRs (about 120 grams lighter than the SLs / thru-spoke-blades instead of hub-spoke design of the SLs).
Just my opinion: Don't get too caught up on the weight. The aero qualities matter much more than the weight.
I found the SLRs to spin-up very quickly -- substantially quicker than the Kyseriums despite weighing about the same. On flats the SLRs were much faster due to the aero design. Where I typically hold my Kyseriums around 21-22 on flats, I could hold the SLRs 23-25.
Climbing goes to the Kyseriums, though. The SLRs were not bad for rolling hills or moderate climbs (just rev up the speed and let momentum carry you up and over). However, for extended hard climbs, the Kyseriums were better without a doubt.
The dish wheel will be much better for riding in groups -- allowing you to keep up speed in the pack with less effort. You can rest more while drafting by having to output fewer watts at speed -- then also being able to pull harder on your turn due to the aero wheel cutting into the wind better at higher speeds.
I'm currently looking to Reynolds DV46 ULs as a alternative to the SLR to give the same flats performance but (hopefully) better climbing performance by being considerablly lighter at the rim...
If I could sum up the two wheels, my opinion would be:
Kyseriums - Rock solid, stiff, very durable, very good climber. Poor aero qualities start to make sustaining speeds over about 22 (for me) hard.
SLR - If the sustained speed is below about 12 (climbing), the wheel feels like it wants to go slower. Over 12, the wheel wants to go faster. Over about 21 the benefits of the dish aero wheel really start to shine very bright. Over those speeds the wheel really cuts the air better and expands one's top end sustained speed as well as sprint/attach speeds. For example, it takes me an all out effort to sprint up to 30+ with my Kyseriums. With the SLRs, such attack bursts were substantially easier -- despite the weight of the SLR being about the same as the Kyseriums.
Last edited by martymc; 06-01-09 at 06:30 AM.