We're more active and don't really sit around much, so the patio would not get much use in our case. If we ever settle down, I could see the convenience of having it off the living area instead of having to climb stairs to go between camper and outdoors (we live in 3-level home, so stairs are natural part of our everyday life).
Some of the campsites we visit are constrained to width and length. Factor this in to your purchase. We like some locations that limit you 30' because of natural physical obstructions and other places I have had to climb the roof and do some pruning to fit my vertical height. Locations closer civilization or near a popular venue may be too narrow to deploy your slides on the left and still drop the deck on the right. This is something we looked at with our purchases so we were not limited where we like to travel.
My dog loves it! I really like it when I'm camping at the beach. Perfect place to have my coffee and sit outside without getting my feet sandy. However, a slide in place of the deck would add a lot of interior floor space. Our TH is 45' long, but it doesn't have a lot of floor space. Any more than 4 people inside at a time, and it gets tight.
Use ours nearly everytime were out in it. We've not used the rear patio at least not yet. The side patio seems to be more convenient with accessing the living space than the rear one. Love ours for morning coffee and watching the news! Doesn't stick out any farther than the awning either. We have the chairs on the ground with ground mat and usually sit around the campfire when everyones up and about, but when we get up in the morning, usually the first ones up, we stay on the patio. Don't think I'd want to be without one either now that we have one!
First time I saw one I thought it was pretty cool, but then I thought if I was going to be sitting around outside why wouldn't I just sit in my chair on the ground. I think it's one of those solutions in search of a problem.
I guess it does beat sitting out on the concrete, but we usually don't stay at concrete campgrounds for too long. Most of our camping is done on grass or dirt so the side patio just doesn't compute.
We are in the process of shopping for our first RV/toyhauler. Our group of riding buddies has many different camping setups from TT's, truck campers, tents, Class A's and Fiver toy haulers. We always seem to gravitate towards the large toy haulers when we're hanging out outside together. It seems to me that the side patio would just get in the way of the campsite.
What makes it so appealing to you guys that love it? (I totally understand the dog issue). I don't mind putting my chair on the ground and being unrestricted in space.
I'd get one in a heartbeat, I think it'd be great, especially with our dogs. One is a senior and can't get down the steps by himself, so a side patio would let him still hang out outside without having to go down the steps. We have the rear patio and it's nice, but it doesn't work on all sites.
We have the Grand Design Momentum 399th with side patio. We use it all the time. This layout has dual slide outs in living room so it feels really spacious inside.