I stayed in one of the last rooms on deck 1 of Sunshine, as far aft as you can go - I think I was in room 1630 or something like that if you want to look it up on the deck plan. The noise from the engines wasn't too bad really. And I didn't notice any really bad vibration either.
The only issue was the thrusters and ropes when docking. That was quite loud and jarring, but only lasted for a few minutes during each docking/undocking operation. The bad thing is docking was typically done fairly early in the morning, so it was a free alarm clock.
All things considered I'd stay on deck 1 again, but only if the room was considerably cheaper than other options, or if it was a last minute booking and I didn't really have another choice (which was the case when I stayed on deck 1 on Sunshine).