My understanding is that the baffle diameter limits the clear aperture at the rear of the cell and therefore the usefulness of 2 inch diagonals on the smaller Celestron SCT's. Per the site below the C8 has a baffle 38mm in diameter and the C9.25 has a 48mm baffle.
http://osastrolog.blogspot.com.au/20...ffle-size.html
Also, just to clarify an earlier post, the 42mm Vixen LVW has a 72 degree FOV, all the other LVW's have a 65 degree field.