No deck stain will last 5+ years. A good quality stain will last 2 or maybe 3 years on a deck floor (horizontal) and typically twice as long on railings, siding, etc. (verticals).

Penetrating stains will have less chance of peeling as they soak into the wood grain and do not film on top of the wood grain when fully cured.

Penetrating deck stains are easier to maintain by cleaning and reapplying after 2-3 years.

Filming Deck Stains that dry on top of the wood can be harder to remove and/or reapply as they are more prone to peeling, wear, flaking, etc.

Not all Deck Stains are penetrating. Even when they claim otherwise.

Semi-transparent, Transparent, and Semi-Solids will show the grain of the wood to some extent. Solid stains, Deck Resurface Coatings, and Paints will not.

Clear sealers without any pigment/color will not prevent UV graying. Lighter Pigmented stains that are Transparent, Semi-Transparent, or Semi-solid will have less UV protection than Darker Pigmented stains in the same transparency. More color/tint = better UV protection.

Deck Stains are either Oil-Based or Water-Based. Filming or penetrating. Transparent, Semi-Transparent, Semi-Solid, Solid (opaque) Stains or a Deck Resurface Coating. See here for more info on Deck Stain Types.

Oil-based stains can still be used in all States as long as they are compliant to local VOC regulations.

When switching brands of deck stain it is always best to remove the old coating first. Do this by using a Deck Stain Stripper and/or sanding.

Always apply a Wood Brightener after prepping with a Stain Stripper or Wood Deck Cleaner to neutralize the caustic.

New Decks (less than a year) are treated differently than older decks (more than 1 year). New decks need to be prepped and usually cannot be stained right away.

Prep, Prep, Prep = increased longevity of a stain.