Bulls Eye 1-2-3 is a water-based primer-sealer that I have used many, many times and have always been pleased with it's performance. It can be used for both interior and exterior applications. I like the time this product saves on paint preparation, because you can apply it without having to sand first. It can also be tinted with the paint your going to top coat with to make the paint a one coat application. It has a quick one-hour dry time for recoating.
I have used this to cover stains, such as water damage on ceilings and it has always done great in covering the problem areas without the stain bleeding back through the paint. Some of the of the other stains it will seal are graffiti, greasy spots and crayons.
You can use this on just about any surface, including glossy surfaces, glass & tile. It can also be used to cover clean iron surfaces to prevent rust. I also like to use it in high humidity areas, such as the bathroom and laundry room to prevent mold & mildew from growing.
This is one of the best primers I have ever used, and I would highly recommend it for all your painting jobs.