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Astrophotographers with beefy mounts, rigid OTAs, and robust focusers should have the fewest concerns over the camera's weight.
Recently I was commissioned by the York Astronomical Society to design and build a very large Crayford focuser for their 300mm aperture reflector.
With its dew shield retracted and no adapters attached to the focuser, the FSQ-130ED is impressively compact, being slightly less than 21 inches (53 cm) long.
In addition to the carbon-fiber truss tube, a trio of cooling fans for the primary mirror, a dual-speed 3-inch Crayford-style focuser, and a pair of Losmandy-style dovetail mounting bars, the scope features both mirrors made of fused quartz.
The ASCOM website includes a list of ASCOM-compliant motorized focusers (ascomstandards.
Both of the 5- and 10-mm models fit 1 1/4-inch focusers, while the 15- and 21-mm versions are 2-inch format only.
In use, the focusing action is a little finer than most single-speed units, and a little coarser than the slow speed of most two-speed focusers," Jerry reports.
As the assemblies rotate in tandem, the spacing between the focusers (and therefore, eyepieces) changes.
I found no wobble or image shift with heavy 2-inch eyepieces or a DSLR camera, though I did not weigh it down with massive CCD imagers, filter wheels, and robotic focusers.