Hayes played every third series in rotation with Daryl Washington in the first half last week. Neither played in the nickel, with Paris Lenon still in the dime package. I thought Hayes looked very good for a guy coming off a chronic back problem and surgery, and it's very likely that he'll take over in a near full time base defensive role soon. I doubt he displaces Lenon from the nickel, however.
That puts him in the Dan Connor, Andra Davis, Rey Maualuga, Keith Rivers, etal tier. They'll play anywhere from 15-50 snaps, depending on game factors, and have games where they'll have 5-7 solos and games where they'll have 1-3. Most of the time those situations will be predictable (I'd expect a pretty even mix against MIN this week -- prob 30-40 snaps for Hayes -- with more upside than downside), but not always.