For the VLC, generally we use a silica with a granulometry of 40-63 microns, while in the HPLC column has a granulometry of 3, 5 or 10 microns which makes we have a better separation. General way the VCL is used for fractionation while HPLC columns (or semi-preparative prepparative) were used for purification.
The same silica is used for vlc and the open columns.
For the brand, I have used only the "Merk" silica that I am satisfied, but I can not give you a comparison. That said chromatography plates thin layer from "Merk" are much better than those from "Macherey Nagel" that have a diffusion problem (especially reverse phase).