I've never seen or even heard of a hybrid with a "king" bed but rear glide king bed travel trailers are common and even more popular than the former queen bed versions. The KZ Spree
is just one of several brands offering rear glides in a number of different sizes and for many this type of expandable trailer is much easier to deal with than a hybrid with tenting. Keep in mind also that hybrid bed mattresses almost always have a seam connecting two pieces which can prove REALLY uncomfortable to sleep on
whereas a rear king slide bed mattress is all one piece, just as is the mattress on a queen walk around bed in a traditional travel trailer, and in fact a popup. Some manage to deal with it but for us it eventually proved to be a deal breaker ... we traded our hybrid for a travel trailer with a queen walk around bed and not only did all my annoyance with having to deal with tenting instantly go away but so did the mattress problem.
Frankly, with so many rear glide king bed models now available on the market I can see only one
really good reason for buying a hybrid instead of a rear glide or conventional travel trailer - you simply prefer sleeping under tenting and are willing to put up with having to deal with the drawbacks in order to do so.