I was a swimmer for 6 years. I'm not trying to be negative about my experience - but the truth is the truth. I have been out for a few years now, and I value the time I spent in the service. I'm going to shoot straight with you: it sucked big balls.
If you are serious about this job, compare the graphs on the following 3 links: http://www.public.navy.mil/bupers-npc/enlisted/community/aviation/Documents/AWO.pdf http://www.public.navy.mil/bupers-npc/enlisted/community/aviation/Documents/AWS.pdf http://www.public.navy.mil/bupers-npc/enlisted/community/aviation/Documents/AWR.pdf
You will see retention among AWRs is significantly lower than other aircrew rates.
Also compare it to the likes of a diver: http://www.public.navy.mil/bupers-npc/enlisted/community/specwarops/Documents/E100_ND_NOV16_WEB.pdf
NPC reveals some good information. I was an AWR, so my view may be skewed of the aircrew pipeline in general. I'd recommend exploring diver or other rates before considering AIRR. It is glamorized in the media and across the web - many aircrewman try to overhype the importance of their job to find some sort of self worth.
To answer your questions: I never conducted a rescue. The only people I know who conducted rescues were evacuations during Katrina. Not sure if you can count those as "rescues". As a junior crewman at home guard (not deployed), I flew almost exclusively at night time. Expect to do 10 hour days 5 days a week. The time before your flight will be spent studying, hiding from your asshole chiefs who from my experience all have mental disorders in some form or capacity (complete sociopaths), preparing training powerpoints, and doing your assigned job which can be from writing flight schedules to logging and tracking certain qualifications. I was not an avid swimmer, and I did just fine. Don't expect to further your education in your first 6 years. I did get 3 courses done while I was in on deployment - 2 intro geology courses and a college algebra classes. You will be extremely limited in what options you have in that department. The military is a sacrifice, and there is no other way to put it. Hope that answers some questions.