We have been using this primer for years as well. Cover Stain became our go-to oil primer because it is thick, and because it blocks out stains like it is supposed to. We most commonly used Cover Stain for bare wood surfaces (especially old exterior wood that is porous and/ or or prone to tannin bleed, like cedar) and for problem surfaces with staining issues. These surfaces include water stained ceilings, smoke stained ceilings, and walls from which wallpaper was removed.
This product does a great job at blocking stains. With wall paper removal, Cover Stain does a good job at locking down torn drywall, and wall paper glue residue on the wall substrate. This provides a safe undercoat for application of a latex product. If latex is used without an oil primer, bubbling of the finish coat, and flashing of the residues is common
Cover Stain dries fast, and can be recoated in one hour, as stated on the can. We do however suggest an overnight dry with oil primers, as they can take some time to harden, and can also take time to off-gas their oil solvents.
Cover Stain's main weakness is that it is very smelly, with intense oil fumes. You must use with adequate ventilation - or you will catch a nasty headache. Also, if you plan to clean your brushes be prepared to spend some time with thinner or mineral spirits.
See our review of GARDZ, which offers a great, water based alternative for wallpaper removal use primer.