Juniper M series/Cisco GSR comparison

Matthew Correll writes:

I'm looking for objective sources for a comparitive analysis between Juniper's M10 and/or M20 routers and Cisco's GSR 12000 series.

[...]

I'm not looking for opinions or vendor bias - only documented testing done by reliable (and hopefully objective) sources.

Cisco appears to have commisioned an independent evaluation of its GSR 12016 series by "The Tolly Group" for what it's worth: <URL:http://www.cisco.com/warp/public/cc/pd/rt/12000/prodlit/tolly_in.pdf> M.