RHC Factory program
 

I'm going on June 4th 2012.
Unless you have a R22, and are a commercial pilot, do the R44.
That's where the jobs are and they fly very differently. Rock vs feather.

Hope this helps.

For fulldowns and limited power stuff, definitely 22.
Raven/Clipper/Astro is more forgiving and easier on the pilot. Doesn't your prospective/future employer have clear take on this? The only other reason for doing it in 44 could be the CFI sign-off coinciding with reaching the required 50/25/200+ hrs and not having to pay extra for checkride for the endorsement if you've done your ratings already.