Well, in reality, all pipe tobacco blends are made so that they are ready to smoke when they are put on the shelf.
I'll agree. . . but I might add, "in theory." I mean, in theory, the above should be true. But some blenders produce blends that truly do taste rough around the edges when they're first released -- even though they may already have years of age on them; it's hard for me to believe they weren't intended to spend even more time melding in the tin before being consumed.
But I think you're typically much more likely to find blends that are good fresh. . . and only get a little better after about three years in the tin.
I could give you a long list of blends I'd recommend, but I don't know how helpful it would be since I don't know your preferences. But I think the current Dunhill range smokes fine straight from the tin, as do the Rattray blends, McClelland, Esoterica, Germain, Gawith & Hoggarth, Samuel Gawith, etc., etc. Now, some may need some drying time when you open the tin, but that's to be expected.
As I type this, I realize that I didn't list one of my favorite blenders, G.L. Pease. For me, Pease's blends are just okay when released; they really benefit from at least a year or two of additional time in the tin. I happen to see this as a promising sign of longevity over the long term, though -- just like the finest wines aren't often at their peak for years after release. But, at least among blends that I currently smoke, I think Pease stands alone in this regard.
Bob