I put a rifle scope on my Ten Point Elite. I've heard more than once that a rifle scope is not designed for the recoil/vibration of the crossbow and the eyepiece will crack where it threads on to the tube.
I figure maybe these scopes are cheap. My scope is a 40 year old Bushnell and I've shot it on the crossbow at least 50 times with no ill effect. Anyone have an opinion on this?

Sometimes the bear eats you, lol. I use two xbow specific scopes but have also heard the same.............

If it's a decent scope then there's no issue.
Also parallax is a non-issue as well. If someone tells you different just nod your head and move on.
BTW, I've shot my crossbows with Leupolds and 4200s a thousand or more shots with absolutely no problems whatsoever.

I've had a Nikon scope on my Excal for years now and no problems.
I personally think rifle scopes are an advantage because of light gathering capabilities...mine has a 50 MM lens