I think EK did a wise thing and made a 360 since just about any mid size case will fit one.... I think Swiftech dropped the ball here. Given the pricing, my first thought was that Swiftech will maintain the lead in the dual rad space and EK will woo peeps away from Swiftech where peeps wanna "go bigger" and get the 360.
OTOH, some peeps will realize that the 2 x 140 Swiftceh unit at $150 provided 90% of the cooling capacity of the $230 EK 360. For my own and user builds, I still prefer custom loops where budget allows and it's hard to recommend the EK over a custom loop kit given the lack of price difference. One thing that both fall short on is Swiftech doesn't do a triple and EK doesn't do a 140mm wide model. And given current case preferences that all offer 140mm wide rads, and the superiority lower price in WC builds w/ 140mm fans I think this will set the tone as being favored by enthusiasts. A 420 is equal / better than a 480 while costing less and uses 2 less fans in push pull.
Just like the 980 Ti doesn't have a lot of market share, but it is the undisputed "king of the hill", that leads to a lot of sales of lower cost sales in the product line. A 420 model would likely "win the title" and therefore drive sales of the lower cost / size models accordingly. Also, I oft recommend against a 240 / 280 on open loop AIOs cause when ya add those GFX card Water blocks....you're wasting a lot of radiator space up on top oft forcing you to "miss that extra 120/140 that "cuda been there" w/ sacrificing any case space.