OK, I'll start.
I own both the nylon-string RO20 and steel-string RO10 Rovers. I play primarily classical guitar, but on occasion have played some folk. I not only like the Rovers for their portability and great case (which has done fantastic in airplane travel), but I have relatively inflexible hands so their scale makes reaches much easier. That said, I still use a full-scale CG for lessons. But sometimes for early music and/or difficult stretches, I'll take out the Rover RO20.
Over the last year, I have tried a couple shorter-scale CGs ... the Cordoba Dolce (7/8 scale, which to them is 630mm) and the Jasmine JC-23 (594mm). The Dolce was lovely, but despite being a solid-top, it sounded no better than my Yamaha laminate. Worse yet, it had sharp frets out of the box. The cheap Jasmine was, amazingly, much better in the fretwork department. Great neck, nicely finished, cute parlor-size body. But, it sounded plastic. I've had a Jasmine steel-string acoustic in a laminate that sounded perfectly fine. This one did not, and it was mainly in the B and G strings. [BTW, I did check - it was wood inside! Smelled nice too ... just sounded terrible on those strings. And yes, I tried new strings].
The smaller scale was not intended to be a travel guitar ... if I liked either, they may have supplanted my Yamaha as my main guitar. But as it is, if I run into trouble with the Yamaha on a difficult stretch, I'll use a capo and tune accordingly.
Having said all that, the Rover RO20 really has a lovely sound all its own. I don't know if it's the shape or the solid wood, or both. I do make a point of keeping it humidified (which I hate doing ... I prefer to leave guitars out, which is why I favor laminates), but since there's really nothing like the RO20, AND it's out of production, I baby it. I nearly bought a backup one but it was a bit too far away, and could not get down to the seller. I do keep an eye out though.
When I was between CG instructors, I played with a local Folk School and enjoyed learning a few tunes there. I had to buy a dreadnought for projection (our "class recital" was at a bluegrass festival), but about a year later I sold that otherwise-lovely solid-top Yamaha dreadnought and kept my Rover RO10. Folk music sounds great on the little steel string Rover ... esp. if you're just at home and don't have to project far. Sadly that one is in its case for the winter too. The styrofoam cases are pretty good about keeping dry air out, so I only have to check the sponges about once a week.
My house has natural gas heat, and gets pretty dry in winter. I'm in SE Tennessee, yet here in mid-November the humidity has already dropped to about 35% in the house last week, and later in the winter, it can get below 20% on the coldest nights. So we really have to watch it for a few months per year.
I love that Washburn still makes the steel-string Rover, though mine is not likely to wear out. I remember when they used to offer some offbeat colors/designs, like the cowboy/western themed one - and lately I think I saw a camo one. If I saw one cheap, I could see picking up a backup or one I wouldn't mind neglecting a bit. Kind of like a sacrificial guitar - keep the other pristine (yet I bet decades from now the rarer weird ones will be more valuable). But I wish they still made the RO20 because IMO there's no good substitute for it. The Martin Backpacker strikes me as inferior in so many ways (except name recognition). I've tried it, and felt it wasn't finished as well, not to mention the lack of truss rod, less-protective gig bag, and awkward shape. Just read recent reviews and you'll be glad you have the Rover.
Sometimes I get tempted by the Traveler Ultra Light Nylon or the Yamaha SLG130NW for silent hotel room practice. But they're so much more costly, and the Rover is so much easier to bring along (esp. in terms of protection). One can just use a string mute on the Rover if silent practice is desired.
That's it from here. You can have my Rovers when you pry them from ...