Here is what I found in field use for users to be aware of.
I encountered two issues with the TVC-24L. Both issues could affect other models.
These issues are easily dealt with once (and done with), but worth noting.
Loose top plate
Article continues for subscribers...
diglloyd Advanced Photography includes hundreds of pages of exclusive coverage and high resolution, Retina-grade example pictures detailing Canon and Nikon DSLR bodies and their lenses, with in-depth analysis of sharpness and contrast, color, bokeh, vignetting, distortion, MTF, and flare. Also included is a wealth of in-context technique and workflow insight. Since 2006, diglloyd Advanced Photography is the authoritative review and on-line reference for discerning Canon and Nikon shooters. Subscriptions cost $ per year.