Having watched/read many (countless?) YT videos and articles, I'm surprised that I've seen virtually no mention of zForce seatbelts (other than retraction issues - due to dirt getting through floor holes). 

How good/effective are the basic z500 Trail seatbelts?  I'm wondering if I should install 3-point (belt and both shoulders) seatbelts i.e. to assure containment within the rollcage ... if I buy one.

thanks, in advance, for whatever insights.

[2015 Z Force 800 53/Trail EPS]

The shoulder harness satisfies the minimum requirement. It is better then nothing on the occasional lay-over but will never keep anyone in place on a roll-over or end-o at speed or multiple roll situation. I put a cheap 4-point set in mine but the wife hated it and wanted the shoulder belt back on her side...so she got it (of course). In honesty, I only wear mine when the ride takes me into a situation where it is possible for a roll-over. Otherwise it's tucked behind the seat. The wife.. always wears hers. 

Insightful answer, NM ... just what I was seeking.  THANKS.