I recently read on Twitter that Yo Sushi are introducing Yo Burger, where instead of having bread buns its sushi rice patty. This is not the first time I've come across this concept, as when I was living in Melbourne I ate at a restaurant called J Cafe who have been making sushi burgers for eight years (blog link) and they made it very well.
YoSushi's burgers will set you back £8, but it does include nori crackers, daikon slaw and misochup. I still think this is a bit pricey, like most things at YoSushi but I am intrigued to try it and compare it to the teriyaki sushi burger I tried at J Cafe. Upon looking at the photos, the only physical difference I see is that J Cafe's sushi burger has sushi nori (seaweed) holding the burger together, which makes me curious in whether the YoBurger will fall apart at your first bite.
I think YoBurgers will definitely get tongues wagging, as its a new concept in England and I look forward to hearing reviews about it.