I prefer PCB Matrix keep independent on the Expedtionpcb. As a small team, They can response very fast to any bug and inhancement requirement. Two weeks ago, I found that Symbol Wizard can't reconginze any implicit pins whiling importing Concepthdl and Dxdesigner symbols. After reported to PCBMatrix, They immediately began to modified the tool to support this. If They have merged with Mentor team, I think you have to waite at least 18 Months to see any action be taken.
Least but important, I wish PCB Matrix can support multiple CAD platforms ,not exclusively to Mentor platform.
Unfortunately, we are unable to make any comments about the Valor acquisition at this time. (If/when the acquisition is complete we will return to this thread)