I have one of these scopes and it is frustrating to remove the lens. I checked my scope and the FL spec did not match the length of the tube I suspect the lens in mine was used to compensate for short tube to give better spec. Again another trap to get into buying cheaper scopes although wasn't really cheap.
(me)
Apart from that I hate having to take out the lens all the time to use my laser colliminator.
Hence I am looking at another scope.