Received my Utopia backrest on Saturday. Looks to be of pretty good quality. Like Strangecloud indicated, it took about 45 minutes to install. I did not have to remove the seat from the scooter.
Here is where you have to cut the seat cover and drill a hole.
The bracket on the bottom of the backrest
How the bracket sits at the back of the backrest
Here is a view of the bottom of the seat with the bracket attached.
Here is the bracket from the top side. Pretty nice design in that there is a groove that fits the backrest so that it locks the bracket and the backrest together
How the backrest looks installed
This is all the farther mine would flip forward. Bill asked about a passenger mounting and I do it the same way as him. I lean up against the handlebars, lock the brakes and hold the scooter steady, and my wife holds onto my shoulder and she swings her leg over my seat to get to the other side and then moved back onto the passenger seat. A little different than she did before the backrest but she had no issue she said. She still has lots of room between her and the back rest and she really loved the storage pouch.
It does leave a little bit of a gap between the bottom/back of the backrest and the seat. I could not believe how much dirt was under the edge of the backrest when I first removed it to install this and it was a tight fit. I cannot imagine how much dirt is going to get under this gap. I might try to fill it by shoving some square black door/window closed cell foam in there to eliminate the gap.
One issue I see is that when you press back on the backrest, you are putting twisting forces on the seat highlighted below. I could see it flexing with me just putting my hand on it and pressing. I can only imagine how much this thing is going to flex when you have the weight of your upper body pressing on it and then hitting bumps too. I can see where this could easily crack the seat pan.
So I am going to have a piece of metal made to put on the underside of the seat pan that will spread the load over the entire area highlighted in red above. Here is what it will look like. This should work pretty well.
While I don't need or want this, this is for my wife. We normally ride two up on this. She gave up riding her Harley about 8 years ago because it was getting to heavy for her so we bought this and ride two up. She misses driving but when she does, her back would hurt but it never hurts when she is ridding pillion resting against the top case. I had a Versys X300 a few years back that I sold and while I loved the Vespas (both 150's and 300's) I had before and after the Versys, I really missed the Versys as I love to ride back roads and gravel roads. We mainly ride back roads (paved) with the BMW but I would never take the BMW down a gravel road. So the trade off was I could get a used Versys and I put a driver backrest on the BMW and the scooter is hers and I have the Versys. If she does not feel like driving, she can ride on the back of the BMW and I will drive.