MartinBaker,
A civilian employer (EMS, off-shore, heli-tours, etc) drive their hiring minimums soley on what will allow them to insure their aircraft and organization most cheaply, which currently is about 3,000TT, 1500 PIC (very round figure). Day for day, an Army Warrant will have more flight time cumulatively at the end of a 20 year career than the average Marine or Navy helo guy. This is due soley to the fact that as Navy/USMC pilots mature professionally, they're forced to complete non-flying tours (ALO, FAC, or ship tours) to enhance their career progressions. Also, as a reward for getting promoted or screening for command, your (Navy/USMC) flight time is again reduced.
The difference being that a Warrant officer will stay in the cockpit every day for his/her 20 years, flying all the way to 30 years if they desire. At my unit, it's not uncommon to have CWO5s (equivelent to an 0-6) flying every day as a regular line/assault pilot passing on all the experience that comes with 20+ years at a set of controls.
Collateral duties as a Warrant are minimal (as your primary place of duty is the cockpit.) What extra issues you are saddled with diresctly relate to flying, (i.e IP, instrument examiner, tactics, safety officer, etc.) There's no flying warrants managing 1LT dept, Navy Relief, AWOL, bounced checks, spousal abuse, DUIs, etc.
My experiences have shown that if you take a Warrant out of flight school and say an Ensign/2LT, and join em' up down the road 5 years later, their comparative flight times will be pretty close. The Warrants pull ahead only during the long haul when upward mobility starts to keep the sister-service guys/gals out of the cockpit.
That said, regardless of service, I've never seen a hard-charging, solid aviator/officer that didn't as much flying as he wanted or could stand over a career (unforseen circumstances not withstanding).
As for how each service trains their aviators is a heated topic, but with some research, one you'll be able to answer yourself. It becomes largely a factor of your personal preferences and what type of environment you want to work in. I will state however, if you don't think having to brush dirt and sand out of your teeth every night before you head to your bunk, eagerly anticipating the warm MRE you'll pull out of your sleeping bag for breakfast before you head off for 5 more hours of mission planning, followed by another night of taking it down town to the "X", than Army/Marine helicopters may not be the route you're looking for. Navy rotary wing is making huge strides and risen to the task, but that bag of worms has been discussed in depth on several threads here.
Probably more than you ever wanted to hear from my perspective...
