Overledger will be hosted on a large number of cloud services AND they will soon offer the possibility for everyone to host their own gateways
This isn't true decentralization when 1 entity controls the hosting across numerous cloud servers. When you say gateways, are you referring to original endpoints providing data or simply just a gateway to Quant's cloud servers?
Is there any drawback though re Xrouter not having to go through this type of work? 2min sounds nice, but is that providing 100% interop?
There is certainly no drawback as developers are free to do as they please whenever they want to - there is no waiting, permission, or green light involved whatsoever. It most definitely is providing 100% interoperability as assets and information alike are enabled to interact and move freely on any dApp imaginable that can be built leveraging XRouter.