Next topic is the loo... [...] It won't be mounted in the camper. We just have a simple slide on set up for our tray. Keen to hear what others are using, we don't want a crap one (bad pun).
We do the same, and love our portable toilets.
We started with a Thetford 135 that was small enough to fit between the front seats of the van:
The "cap" on it served to strap it down during driving (and made a nice center console), then doubled as a riser to get it up to a more useful height. The downside of the 135 is that the waste tank was
tiny at 2gallons. With 2 adults and 1 child, it barely made it through 3-day weekends in the desert.
So.... when I built new cabinetry for the fridge, etc. in the van, I made sure to leave a space big enough to put a much larger portable. I currently use a Dometic with a 5 gallon tank, and it's awesome. The box is built large enough that I can also fit a Thetford 550 which has a 5.5gal tank.
The only toilet I couldn't fit is the Thetford Curve (also 5.5gal), but a little too tall for the cabinet I could build. The Curve is the Cadillac of portables. It sits at normal toilet height and is super comfortable. (Though my Dometic is very nice as well, and due to the way I have it mounted to slide-out onto the tilt-down cabinet door, it sits very close to household toilet height also.
We've never had any smell issues with either of our toilets, and you'll note that they ride inside the van with us. (And with the new cabinet sits right at the foot of the lower bed!) Biggest issue is the sound of the fresh-water flush tanks "sloshing" on rough roads. Generally, the portables are very easy to empty into any standard toilet (or vault, etc.). There's always an "anti-glug" valve of some type (differs with manufacturer) that keeps everything from splashing, and the rotating dump tube is very convenient. I generally add water and "swish" for one rinse and a second pour, and I'm done. You'll want to use one of the many commercial RV waste tank chemicals sold as "deodorizers" that serve the vastly more important task of breaking down the solid waste so it "pours" well. There are a variety of brands and formulas. I've used the Thetford name brand stuff as well as whatever they sell at Wal-Mart, all work fine for me. Similarly, you'll want to use TP that breaks down relatively easily in liquid. Either name brand "RV" paper, or septic-safe paper is generally fine. This is especially true if you know you'll be dumping in a septic system (i.e. at home) or if you want maximum flexibility for dumping on the road. (I would consider it very rude to dump my tank with non-septic-safe paper into someone's toilet that went into a septic field, for example.)
Note that the one downside of a huge waste tank is that you need to be able to carry and pour 40lbs of crap. (Literally.) If lifting/carrying 40-45 pounds will be hard for you, then you'll want to opt for the smaller tank or dump before you're full.
Lastly, there are all the "creature comforts". The most basic models have no tank gauge and a simple bellows pump for the flush water. In the middle range you get a tank gauge and some sort of pressurized flush pump (either manual or battery powered). At the top-end they're generally all battery-flush, etc. Some models (usually labelled "marine") also include hold-down brackets if you desire to actually fasten it down to something. I just put it in a latching cabinet, since you'd have to release the hold-down brackets to dump it anyhow.
Hope that helps.
