I am 6'2" and the length of the T2 plus is great (same length as the T3 plus). Lots of extra room... You'll be fine at 6'4" with the length. The width you can only truly figure out by checking out the tent in the store. Or at least measure out the width and lay in that space with your wife to see if it seems doable. You'll love the height of the tent (44 inches). That's no small concern for a tall person.

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