Do you think the difference is more to do with the bike your riding and the weather conditions? I know I always feel quicker on my summer bike than winter bike, I definitely climb better on my summer bike, but that's because I don't have my rucksack on like Monday to fri on my winter bike.
I ride both bikes to work, usually the winter bike, but with baby no.2 due any day now, I'm riding the summer bike to work to get some mileage on it as I don't think I'll be getting out much this summer! I still think the Aksiums have the edge on the Fulcrums, but the Fulcrum hubs and freewheel are easy to service - I had to do this after 1,500miles over winter.
Got my fulcrums today, put them on tonight, they look good on my bike, matches in well with the red hubs
Pics please!

Full wheel packages are great for weekend/race/training use...
If you ride in a city, lots of stop start, all weathers, then handbuilt are cheaper long term.
I'd thought about handbuilts for my winter bike/commuter - it had CXP22/Tiagra hubs/SS spokes but the freehub went kaput and the bearings were shot. My commute is my training time and generally I touch the brakes only a few times as it's mostly on country roads - I agree that rim wear would be an issue if you're commuting in town, I reckon I'd go 700c disc if that were the case.