I am using JBoss Native in production. But there is no difference in performance or reliability between the JBoss Native service mechanism or Tanuki service mechanism. Both simply launch JBossAS which does all of the work from then on - the service launching mechanism takes no part in anything beyond that.
Note, however, that JBoss Native, when installed, provides the Apache Portable Runtime (APR) which can speed up HTTP rquests. But of course you can install JBoss Native for APR and still use Tanuki as the service mechanism.