I love Vario stockpages. I use a few thousand to house parts of my collection.
I think they are great! However, be forewarned of the following potential problems:
1. One sheet may seem thin and light. But get up to 100+ and you will realize they really bulk up your collection and can get quite heavy. Make sure you have strong bookshelves and strong binders (avoid going past 1½" binders, as it gets heavy and bulk turning of pages can be difficult when there are too many. My Varios take up about 5 linear feet of shelf space, and I pretty much have to use minimum 1¼" thick solid wood shelves (not particle board).
2. The page layout is rather fixed for each strip. You want the strip to cover each stamp completely. This can be rather difficult when there is a mix of stamps and souvenir sheets within a set. So if you collect a lot of modern stamps, it can get rather jumbled. On the other hand, classic era stamps tend to be of uniform small size, and many commemoratives of the 1940s-1960s also tend to be uniform medium size.
3. Stamps are easy to insert, but can be difficult to pull out because the page surface is so smooth and hard. Sometimes you have to slightly flex the sheet and get a minor bend so that the edge of the stamp lifts up.
4. Sometimes the pages do attract dust. So keep your binders in a dustcover, or at least put a piece of cardboard or lint-free cloth over the tops of your binders.
Best wishes!

k