This one is pretty much the 'Ultimundo' model without the internal brake routing or the head badge. The big S-3 down tube and tapered fork give the bike a really stable and sure-footed feel-great on those high speed descents.
The bottom bracket stiffness is also really good with the oversize down tube, especially for a sub-4 lb. steel road frame. This model will change when I run out of S-3 tubes some time in the next year or so. I ordered heavily on these last week to ensure at least 20-25 more of these will be available before the tubes are extinct. I will most likely substitute a Columbus 'Spirit' down tube for 2018 unless I find a US tube that mimics the shape and properties of the S-3. Vari-Wall is a company that might try to make a similar tube. I have some of their samples in the shop I will build a prototype with some time in the next few months.