<delurk> The unit abilities are really useful in turning the tide, warrior monks' war cry can break multiple wavering units. The no-dachj banzai ability just plain rocks too (a single unit managed to take down 3 groups of samurai bowmen on my last Kyoto seige - I've got to try a Date campaign and see what they can do.) And the Yari samurai speed increase makes them perfect for intercepting flanking cavalary.

I've been very unimpressed with cavalry as a whole - compared to Medieval at least. Swooping crane (Cantabarian circle) may help out horse archers some, but bow samurai seem much more useful.
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