WLP004 covers the same stylistic ground as Wyeast 1084 — a fuller-bodied, lower-attenuating Irish ale strain suited to dry stout and Irish red ale, contributing real malt-forward character rather than the cleaner, drier profile a Chico-lineage American strain would bring to the same grain bill.
At 69-74% attenuation, WLP004's range sits close to 1084's 71-75%, and the practical differences between the two come down mostly to format and flocculation: WLP004's medium-high flocculation rating gives it somewhat more reliable, faster clearing than 1084's medium-high rating at a comparable point, a genuine if modest convenience for a brewer wanting to package sooner.
Irish stout and Irish red ale are WLP004's clear homes, typically paired with roasted barley and flaked barley in a dry stout recipe the same way 1084 commonly is — the yeast's own fuller character does real supporting work alongside those grain choices, and swapping in a cleaner, higher-attenuating strain instead tends to produce a thinner, less traditionally Irish result even with an otherwise completely unchanged grain bill and mash schedule. As a liquid strain, WLP004 needs the usual viability discipline any vial requires — checking the manufacture date and sizing a starter to match its actual age rather than assuming full freshness by default.