Switching from “XPO over Web Service” to “XPO over IIS hosted remoting” made select operations 20% faster for the average usage scenario in xLim. Adding Forms Authentication on top of the remoting didn’t have any significant impact.
Note, that in this test scenario the remote server was located on the ASP.NET Intermediate shared hosting plan in CrystalTech data center. Desktop Smart Client was located on the opposite side of the Earth. If we remove the distance factor (ping between these two points is 245ms on the average), then the speed improvement for this scenario is 26%.
No optimization to the HttpChannel code has been done. Although, probably bringing over the compression logics from WCF would yield better performance results (at the cost of CPU load).
Update: sample can be downloaded here.

Rinat, do you have an example you can share with regard to xpo over http remoting. I have set up a 3rd party provider that supports .net 3.5 and mssql 2005 and have used web services, can you share a brief step-by-step (or point me to a link) that describes how to get started with WCF technologies.
TIA, Linton
Linton,
Unfortunately I have not used WCF beyond the “do it yourself in 5 minutes” samples (i.e.: http://www.codeproject.com/KB/WCF/wcf_bohansen.aspx), so I can not be of real help here.
XPO+Http remoting - I’ll assemble simple autofac + XPO + Binary Http sample by the end of this week.
Best regards,
Rinat Abdullin
Can you send me the code that you send to Linton? or if you have it a basic example on have to host xpo datservice with a sql provider in ISS
Another thing, can you explain what xlim is? I have read you post but it’s to hard core for me.
At the end I would like to ask what you meant with the statement that XPO is not enterprise ready - can you give a top 5?
I am going to port a very large old VB windows application to .NET and have looked at CSLA and NHibernate any advise on what to choose?
Linton, Martin, check my latest post.