I went solo in about 7 hrs. We were expected to complete a full circuit and be competent in dealing with likely emergencies. I already had a few fixed wing hours which certainly helped but I wouldn't say it would be worth missing rotary time if heli's are your final aim.
It's well worth blagging as many hours as possible as a passenger in either planks or rotary just to get used to perpective of things from the air. Maybe even help out with the nav. Spotting airfields etc... can be devilishly difficult before you've 'got your eye in' and it's useful developing the skill as the non-handling pilot.
Have a chat with your local flying schools. There's bound to be a few people hour building towards a CPL who'd be glad to have someone along to chat to. 100 odd hours bumbling around in an R22 on their own will probably be driving them a little crazy!
