I agree with Branchman that you should have a backup - and the Sani-Con accounts for that. Should the unit break, you can attach the "regular" gravity hose and it will work as it was set up originally. I always keep one in the coach as the motto of RVers should be the same as Boyscouts: Always prepared!
That said, before making the purchase (of either the Sani-Con or the Motorhome) I did my research. Nearly all failures of macerators are due to putting the wrong things down the toilet. No sanitary items, nothing hard that would bind up the system. When reading posts about the Sani-Con system, every failure posted was caused by the owner doing something they shouldn't. That, and my friend's decade-long experience (and my year-long experience) without failure leads me to believe it's a quality system.
Of the potential system failures of the FR3, it is at the bottom of the list. I'm far more concerned about the stairs breaking, windshield leaking and slide outs breaking.
It's certainly your call, but gravity rules and things don't flow uphill.