Another "S" model is clearly the best
As an avid fan of the venerable H-3 and with a few rescues under my belt in them, I can only say that most comments about it being a bit (alot!) outdated are certainly valid. In fact, for effectiveness, the Sikorsky "Hawk" family SH-60B, SH-60F, HH-60J, etc are excellent platforms with better speed, reliability and range, not to mention better nav systems and crisper auto-approach/hover systems. However - one aircraft that surpasses them all is not primarily - or even secondarily or tertiarily a rescue platform. Its the 53E which has never really done any rescues but is immensely capable with an obviously awesome cabin (enough for mass rescues or a full hospital clinic for small #s of rescuees), superb speed (150-170 kts), excellent IFR and auto-approach/auto-hover systems and long (MH-53E has 22,000+ lbs of fuel plus unlimited range with air-refueling enroute. The single rescue hoist (winch for the rest of the world) could be augmented with 1-2 aft ramp winches (hoists for you yanks) for redundancy. And the rescue capability of the 53E series is proven in training/demo operations. With the 53K coming, who knows what's possible but it would eclipse most anything else...