Is Zinsser 123 primer better than Kilz?

Is Zinsser 123 primer better than Kilz? Zinsser Bulls Eye 1-2-3 primer is often considered slightly better than Kilz 2 All-Purpose for general use, though both are good all-purpose water-based primers. Zinsser 1-2-3 is known for better adhesion on difficult surfaces like glossy paint, PVC, and tile without extensive sanding, and good stain blocking for light to medium stains, low odor, and 1 hour topcoat. Kilz 2 is also low odor, easy cleanup, good for drywall, wood, masonry, and light stains, and is cheaper and widely available at Home Depot. For heavy stains like smoke, fire, and pet odor, neither is ideal, you need oil-based Kilz Original or Zinsser Cover Stain or shellac B-I-N. Comparisons show Zinsser 1-2-3 may have better hide and adhesion on slick surfaces than Kilz 2. However, for new drywall, both perform similarly, and Kilz may be more economical. So Zinsser 123 is often rated better for versatility and adhesion, while Kilz is good value. For severe stains, Kilz Original oil-based may be stronger than Zinsser 1-2-3 water-based, so better depends on which Kilz you compare, 1-2-3 versus Kilz 2 water-based, Zinsser has slight edge.