Might be ok for occasional use, but it looks like the special bags you have to use are 'single use', & they are not exactly cheap. So just for a three week trip for two people you'd be needing to carry a supply of say, 45 bags, at a cost of $72! I note that the bags are compostable (as opposed to biodegradeable which can take up to 2 years to degrade), BUT they say 'can be disposed of in rubbish bins...... you'd have to hope those bins were going to be emptied pretty regularly! Compostable bags can be disposed of by burying, or in long drop toilets, but it is not clear how compostable the polycrylate crystal sheets are.
In the past we used a similar idea, with one of these types of
toilet seats & some
compostable bags. (Maybe worth trying some with the Bog in a bag seat) We found that one of the larger bags easily lasted two of us for up to 5 to 7 days if camped in one spot. (We also had a supply of smaller bags for overnight stops). A small container of lime (very cheap) with the equivalent to a handful sprinkled after each use ensured smell was not an issue. A piece of cardboard (or similar) laid over the top of the seat when not in use kept flies away. We buried ours, but would have had no problem putting them into a long drop. Only issue with bags was transporting them when full. Ok with solids only, but when full of liquid not so easy. We only pee'd in the bags when we were able to bury them without needing to transport them.
We had planned to use this arrangement for long term travel to avoid the need for being tied to camp sites with toilets, or the need to squat. (Old knees). However as it was, as soon as we gained a little extra storage space when we bought the Tvan we changed to a Portapotti. Altogether far more civilised & environmentally sound when the chemicals they sell for them are avoided.