Pros: wood, very little plastic, attractive, lightweight, compact, easy to install, good for montessori style eating
Cons: not as sturdy as traditional booster, not very supportive
If for some reason you need a booster seat that is easy to transport this is the one for you. Yes, its more expensive but its not an eyesore either-- it is definitely the most attractive booster seat on the market and since I have to look at it every day I really appreciate that fact. Its very portable because it folds almost flat and is mostly wood and metal with a plastic back.
(I have the model by Minui--also Danish--before it was bought by Stokke but I have seen the new one and they are almost identical-- the Stokke version looks a bit more sturdy.) You can buy a stool that it attaches to if you like, but it attaches to every single chair I have ever tried to hook it onto so that seems really unnecessary. Unlike the chairs that hang on tables you don't have to worry that it won't fit. I used it with my daughter from about 6 months on and she was able to sit in it from the beginning although she was a bit wobbly at first--this is no bumbo like contraption you baby has to be able to sit on her own--she is not going to fall out if she can't but she is not going to be that comfortable in the early months either. I was okay with this as she wasn't in it for very long and I figured it just helped her build up her strength.
That said, I think a traveling high/chair booster, falls into the category of things no one really needs. I bought it in lieu of a Tripp Trapp because we thought we were going to move abroad, and I wanted something we could easily take with us. We did not end up moving, and so I really wish I had just shelled out the extra money for the Tripp Trapp, I have taken the Handy Seat out with us exactly 2x. I usually just sit my daughter on my lap, a booster seat that my friends or family or restaurant provide, or more recently directly on a regular chair--she is almost 21 months now.
One more thing you can buy an extra set of legs for it so that it can go on the floor which would make it a great chair for those doing Montessori style feeding-- (teaching their children to feed themselves at a child sized table.) Most children's chairs are too tall for babies, but this one is not and would serve a double purpose making it more economical than special Montessori chairs. (Of course you could always buy a cheap ikea child's chair and saw off some its legs for very economical way to do it.)