lv1 inn is the best for base stats that don't need to be replenished; they will have one stray stat at most; easy to get 69 stat heroes from there w/o need for holy juice.

However, high lv inns (lv10 especially) do give better base stats, but it requires lucky guesses and a lot of holy juice. I've heard of folk get 75+ base stat heroes from an Inn10.