Just googled that item; for the reference: are we talking about the 'monowalker fatmate'?
At first glance that thing may well handle most parts of the scandinavian parts (while a two-wheeler would definitely fail). However, I think you will have to use its rucksack option from time to time due to swamps, river crossings, a short climb, etc...
Actually, swamps are everywhere, but yes, typically you'll encounter those more in the valleys than in the mountains.
To get an impression of the rock fiels, you may watch
her video
(beginning at 9:18, you'll see the huge stonefiled west of Caihnavaggi -- in my opinion, one of the most annoying and dangerous ones, but there are plenty of those along the trail), or you may watch all her videos to see how the trail looks like.
Anyhow, I am not sure whether the weight savings are significant, and this thing seems to be pretty expensive. I, personally, would rather invest in a lighter tent, a lighter sleeping bag, etc. Needless to say, leave any maybe-useful-at-some-point-stuff home! How much weight are you planning to carry?
On the other hand, it would be interesting to read a report after your trip how that experiment turned out