Thanks, Bryan.  This is good to know as I also image with both of my scopes but usually one at a time.  Your combined weight on the mount sounds about 70 lbs vs. the 50 lbs mine (minus accessories) would be.  So, this is very encouraging news.  I have been guiding, up to 10 minutes, with an OAG on the C11 and I use this also to guide the refractor with no issues as I am not using APPM-APPC.  So, this is something else I can explore.