Why do it?  

Why take the job? It's true that time in an S-55 won't get you a job flying an EMS 350. But the old Sikorsky is a unique, interesting helicopter: Big radial engine, no throttle correlator to speak of, primitive systems and a 7500-pound max gross. Oh yeah, a deafening roar that'll wear out the batteries in your noise-canceling headset faster than those in Madonna's vibrator. So while the S-55 doesn't have any modern equivalent, it's just kooky enough to get some respect from future Chief Pilots, especially if you can accurately recite the starting procedure, which means you probably really did fly it. Plus, there's a turbine conversion, which they have three of, that everyone wants to get time in.

As for flight time, I always let my copilots do all the flying.They were Commercially-rated and current, and so could legally log the time. And yeah, some years were slow, but some seasons we'd do 75-100 hours. Flying an old relic (that my father flew in the Korean War) might not be your cup of tea, so don't do it!  But for an adventurious pilot who wants to try something different, it's a pretty cool thing to do for two months if you have the summer off.  (And no, the "SIC's" don't get paid, but the PIC's do.)