In this work we study a two-user multiple antenna system under quasi-static fading employing a novel scheme that combines cooperation and iterative multiuser detection based on minimum mean square error estimation. We investigate three different receivers: a joint detector for the two users, a separate (per-user) detector, and a distributed matrix-Alamouti detector. We show that the separate detector and the distributed matrix-Alamouti have close performance but different detection complexity depending on the antenna configuration. Frame error rate performance under Monte Carlo simulations is finally shown.