Recently I purchased the TruVativ Omnium crankset to replace my FSA Carbon Pro Track's.
Out of the box the cranks had an excellent appearance and looked very well made, no cheap machining lines or marks, it was all very smooth. FWIW even cheap cranksets have this down for the most part. The stock chainring is a 48T, 144mm (bcd of course) by 1/8". I replaced it with an older 'black' Dura-Ace 46T (1/8").
The installation was straight up. You open the BB cups, asses the information for what type of use you're going to ride, and then screw them in. The literature included with the bottom bracket states that for Track use, not to use the included spacers. This will yield a 41mm chainline. Cranks were just as easy to install. Since this setup uses an external bearing BB system, you bolt the arms directly to each other, as the spindle is attached to the arm on one side. This is where the extra stiffness comes in - essentially you are bolting the arms to each other, or using one bolt, whereas in a traditional system, the bottom bracket is bolted attached on both sides and works as the 'middle-man' so to speak. Because the arms essentially rest on the bearings themselves, it is important to use a torque wrench during the installation. TruVativ suggests torquing between 48 and 54nm, I torqued down between ~50-52nm.
Unfortunately, my chainline is off by ~2mm. I am running a Dura-Ace 7600 Hub w/ a Miche Cog. However, this should be alleviated by moving to a Dura-Ace cog, which is about 2mm further out than the Miche. My chainline distance on the rear will go to 42.45, from the 41.25 it is currently at - these numbers are calculated from here. Interestingly enough, my chainline should be pretty much dead-on using my current setup (41mm front, 41.25 rear) but it is off for whatever reason - either the calculation or the literature.
Now, for the good stuff - How much stiffer are these cranks? Are they worth the cost? The weight?
First, I'll be completely honest: I did not notice a difference in the stiffness of the cranks. I don't do match sprinting for a career or anything, but I have ridden for a bit now, and have ridden the FSA's for about a year as well. I did move from 165mm crank arms to 170mm crank arms, which was noticeably more comfortable.
For the cost, they are cheaper than the older, reviewed, FSA Crabon Pro Track's, and certainly less expensive than the newer Carbon Track's. For weights, the Carbon Track's are listed on QBP as 809 grams for the crank-arms (including ring) and the TruVativ Omnium's are listed on QBP as 825 grams. The bottom bracket for the Carbon Track's is listed on QBP as 249 grams (Platinum Pro Track, fully adjustable) while the TruVativ GXP BB weight is not listed (nor could I find it on the SRAM/TruVativ website). Since this would be cups only, I would be shocked to see it weigh more than 249 grams, and believe the complete setup to actually weigh less than the FSA Carbon Track setup.
In closing, I believe that the TruVativ Omnium's are the best buy for Track/Fixed-Gear cranksets right now. They weigh less than FSA's nicest carbon crankset, and have a stiffer design, as well as cost less. The only downside is that the chainline with the TruVativ Crankset is NOT adjustable, and either the literature or calculations are off (I hope the latter).
About the reviewer: I've been 'seriously' riding bikes for about 3.5 years. This is when I purchased a Trek 2500 to start riding. I switch up my riding between a Trek 2300 (Warranty), BMC Streetfire (Campy Record) and my Trek T1. Currently, I wrench at a shop in Virginia.
Street/Bullhorn weight - 16.75 lbs:
Track (Easton Carbon Drops) Weight - 15.25 lbs:
*Weights were rounded off to nearest quarter pound.