I've been wondering why I have not been able to hit the sort of speeds on descents with my current bike compared to bikes in the past (I had taken a break from cycling for about 5 years). I weigh about 10 lbs more, my kit is much more aero nowadays, my helmet is aero, my wheels are 45mm deep instead of 25-28mm depth, my bike weighs about 3 pounds more, I typically carry a lot more food and water and I'm still not hitting the speeds I had been. Learning about the differences in Chinese geo vs Western geo yesterday when reading about these frames made me realize the frame I'm on now is much more 'western' and the frames I had been riding previously were Chinese geo. So all those new advantages in weight, equipment aero are nothing compared to the more aggressive body position Chinese frames will put you in. Something I found interesting. I'm typically topping out at 4-5mph less on many of my regular descents in a tuck now vs a tuck then.
The "race bikes" of today are basically the same exact geometry as "endurance bikes" of 10 years ago. The new SL8 is extremely close to the 2012 Roubaix in geo.
Just to point out, the prevailing trend is to fit higher stack, longer reach, narrower handlebar, minimum saddle setback, shorter cranks. Basically to try and achieve the same (or more aggressive) hip angle as you'd get from the old slam-that-stem bike-fit, but move the arms and hands further up to make the aero hoods position easier. (see Victor Campenaerts's latest Orbea Orca video)
I've been racing for 16 years and have adopted the new fit trends, and can attest that since then I'm typically topping out 1-2mph higher, and easily setting PRs on flatter/rolling segments, despite being fatter and slower than I was a few years ago before making these changes on my new bike. If you find yourself going slower on a modern bike I really suggest you go over your handlebar position and try to get longer and narrower.
My Seka's Exceed geometry has a fairly high stack (although is now actually quite normal compared to Cannondale's S6E, or the Tarmac).But a big knock I'll give it is the short reach and relatively laid back seat tube angle. To achieve the "modern" bike fit, I have struggled to fit a properly long stem, and have to slam my saddle all the way forward on a zero-setback seatpost. The Spear seems to have at least addressed these two shortcomings with slightly longer reach and steeper seat tube.
Have to wonder how much of these new crop of "high dollar budget" frames are just dumping loads of cash into presentation/marketing/website and are basically the same deal as other frames more in the 700-900 dollar range.
As a Seka owner that's fairly active on the WW thread, I'm convinced you're paying for higher quality finishing kit, paint, warranty, and a genuinely better frame. Better doesn't mean perfect--I indeed am one of the people who suffered from the loose seatpost issue, as well as an unrelated frame-creaking issue that required warranty replacement. Take a look at Ribble, similar price-point, but there's a well-known WW thread documenting some pretty terrible quality issues.
If you look at the competition there really aren't many/any options offering a 700g aero-optimized/tested standalone frame at this price point. My big concern is that the price point is getting so high that you might as well buy a domestic name-brand frame. Building up a Spear with Ultegra Di2 would run something like $6000-7000? You can get a new Cannondale S6E with Ultegra for less. I think Seka realizes this, which is why I believe Seka isn't pushing hard on selling in the western market.
