I just replaced mine last week. It was a nautilus too. It lasted over 4 years.
I picked one up from total battery for $110, when same the one at crappytire was $140.
Only used it once, so I really can't tell you if it's good or not.
Edit: to add a bit to Terry's post. It's also good to make sure your battery is mounted properly in your boat. If the battery is bouncing around, and banging off of things in your boat, it will reduce the lift as well.