Chamberlain - Warmest of the 3, but also bulkiest (25 oz)
Sitka WS - Most durable, wind and water resistant also very warm fairly bulky (27.3 oz)
KUIU PRO - Most packable, lightest (13.4 oz)
The Sitka is actually the heaviest weight wise by a couple oz. But it is because of its shell. IMO it is less "bulky" than the Chamerlain. I do not feel like I have to "baby" the Sitka. The other two don't seem nearly as durable with regard to the shell.
I wouldn't try to hike in any of the three, but for stationary work, they will all do fine with the Chamberlain being the warmest and bulkiest, followed by the Sitka followed by the KUIU.