We 'inherited' a Splendide single vented unit in our new-to-us Jayco Designer, and didn't think we'd use it much at the time. Turns out to be a high value item for us. Loads are small, but we just end up putting in a load every day or two. Advantages for the single unit are that you can load it up and take off, not having to move the laundry from washer to dryer when the cycle is done, very small footprint, uses very little water and detergent, and we don't have to spend a day at a laundromat, tossing in a ton of quarters in the process. We've also noticed that with the ability to do laundry on an ad hoc basis, we carry less clothing with us which saves storage space.
The only disadvantage we have noticed is that the clothes come out fairly wrinkled. Others have gotten into the habit of partially drying their clothes and finishing them off by hanging them outdoors on a clothesline, which is something we prefer not to do. As for us, we carry along a small clothes steamer and use that for the permanent press.
As for comparisons with stackables or side-by-sides, I have no opinion as we do not have the space for those options. Might be a very good alternative, but you would have to move the laundry from one to the other when the was cycle is completed.
Whatever the option available to you, I would definitely recommend it as a great thing if you have the space and funds, and are frequently on the road for more than a couple of weeks.