Dosing over a longer period of time would be better IMO since HGH is a long term compound. It isn't exactly like you will kick start anything as it takes awhile with gh anyway.
The 5 on/2 off is "usually" for economic reasons yet sometimes some people think it does help to keep your natural pulse alive and well
How long do you plan on this?
and ps: starting out with 3? do you feel sides? if so, cut back a bit then ramp back up....