Well apart from whizzing around Poole harbour, Plymouth Sound and the North Devon coastline on a rigid raider, I only ever spent 3 days on a ship.
Most of the time I flew around the place in the back of a herc.
Navy medics differ from Amry medics, as our training is primarily for a ship, and without any support from a doctor etc. This translates to working with the Marines in that there are less medics in a commando unit than in a typical Army Battalion. Each commando company will have a medic and then HQ company would have a RAP manned by two medics plus a Doctor. (I think this may have changed with the new organisation within commando units, the RAP may be with the log coy now)
Anyway the manpower hasnt changed.
Army medics dont tend to work alone, and dont do as much clinical work as a RN medic.
Going back to your other thread and a question you asked there. In peacetime when a commando unit is in camp, a medic will join all the other medics from their companies and work in the unit sickbay. Here you will have one medic doing treatments (running sick parades, medicals etc) another working pharmacy, another working front desk, another working hospital appointments, and a PO level medic sipping tea in his office

and a doctor asleep in his
You tend to rotate the tasks so each medic does a stint in each role.
Also companies will deploy individually, wether in support of another unit, on exercise, or adventure training etc. If your company goes so do you with it.
Medics will also rotate through different units just like marines do, to get experience etc. You may find yourself at Commando Logs in the medical Squadron, attached to the SBS or the BPT, back with the navy for promotion or further training courses etc etc. You can also do RM courses such as para training, driving, signals courses etc. I did a few sigs courses with the RM, the RN and the army.
I was also lucky in that I served with 59 Commando (an army unit attached to the RM) this was different again as I did treatments and admin and deployed with the squadron, they share a camp with Commando Logs so I also worked in the sickbay there (I also served in commando logs)
When you deploy operationally you go with your asigned company of marines, work in the RAP or deploy with med squadron in the field hospital. You may also find yourself working in smaller groups if theres a task that is considered dodgy enough to warrant a medic.
You can also like I said deploy on adventure training exercises around the world, wether its climbing Mt Robson in Canada, jumping out of planes in Florida or skiing etc etc
You can also find yourself drafted to CTCRM as a medic in the sickbay and get yourself attached to a training team, so when the nods are out training you do blister checks, sick parades etc in the field.
Whats unique about commando forces from my experience is that you can do the role in a variety of settings, with different units doing different tasks. You also get alot more responsibilty than an Army medic. Even Airborne or SF attached medics.
You will also have to keep on top of your infantry skills as before someone falls over you are expected to join in the slog of the unit your in, things such as sentry duty, signals watch etc etc
If I was thinking medic I would consider the RN/RM. The only down side is if you goto the RM and they dont like you, you may well find yourself drafted to sea, as ultimatly you are in the Royal Navy.
If you go army medic you can of course do the AACC and work with 29 or 59 Commandos.
Hope it helps
Doc