Either scope could work, but...
Only looking at weight is oversimplistic. It's a crude measure of what "might" work. What actually will work depends on focal length, a whole lot. Focal length magnifies tracking errors.
F number and your skies play a role. Faster scopes and/or brighter skies shorten subexposures. My 400mm F2 RASA in my Bortle 7 skies works perfectly on the CEM60, I only guide to minimize eccentricity. The weight is almost irrelevant.
So, forget the guesses based on weight. Find people who've used those scopes on the mount, and see what actual experience is. See what focal length they're working at, whether or not they use a focal length reducer. That's the way to decide.
I've had a CEM60 for years. A TS130 F7 (about 30 pounds total weight) works fine, but it's only 910mm. It also supported a 6 inch Ritchey Chretien at 1360mm, but the total weight was only about 25 pounds.
This is typical DSO AP (and typical CN). Theoretical analyses only take you so far, the situations are complex, results all too often are driven by what factors you put in, what you leave out. Actual experience includes most all the relevant factors, it's much superior.
Edited by bobzeq25, 12 April 2021 - 03:19 PM.