Wow, Gordon's pic looks great. I agree that the plane will probably be all right on its own, however the ripper shanks are certainly a nice piece of insurance.
In regards to the top and tilt, I posted about this in the John Deere forum. Long story short, I was ready to add this option to the 4720 I just ordered until I was told that it would add an additional $3K to the total. Needless to say, I passed on the option.
Truth be known, I have had my 4310 since 2002 and have gotten to be pretty good with a neighbors box blade without using top and tilt. Yes, you sometimes need to make several adjustments and yes, it can be pain to get off the seat a few times, however that pain is not worth 3K in my mind. And from what I am told, a Land Plane typically needs even fewer adjustments than a box blade.
I guess I will find out soon enough.