Unlike the situation with steroids, I don't have years worth of examples to draw on from those I've worked with: in fact, I've never worked with anyone to any extent on GH, IGF-1, or GHRP-6: the first two principally because there is so much individual variation that in my opinion advice cannot be very specific.
With GHRP-6, it wasn't around when I was working with a lot of people.
My own experience with it is modestly positive.
I have a suspicion that it likely is of more benefit to an older lifter (40 or more, or to some extent perhaps past 30) than a younger one, but there are guys in their 20s who like it.
I would not look at this as a way of averting losses post-cycle.
Aside from the fact that it's not very strong, rapid and substantial losses come from these things:
1) Crash of androgen levels post-cycle to very poor levels. This is entirely avoidable.
2) In some cases, an attempt to maintain volume of work and total workload that was doable on steroids but is not appropriate post-cycle.
3) Confusion of water weight loss with muscle loss: water that is just plain bloating, and/or what I call androgenic water retention: additional water stored in the muscles as a consequence of the muscles storing more glycogen (according to my theory) when using anabolic steroids, assuming carb intake wasn't too low.
4) Assumption that strength loss will occur, resulting in change of training that abandons using similar weights as used during the cycles. Which then results in actual strength loss.
5) In some instances, a lifter will put up considerably more weight IMMEDIATELY on having androgens in the system. This cannot then be from the muscles actually having changed so rapidly, but from their nervous system having been underperforming -- goldbricking in the gym, basically -- and then the lifter actually doing what his muscles had been capable of doing anyhow, but weren't. When this is the situation, withdrawal of added androgen can have the reverse effect: the body may immediately return to putting in only half-assed effort. This is, I believe, mental or at least neurological and proper powerlifting training can fully address this.
I would put the focus on whichever of these five issues may be relevant in your case.
The GHRP-6 is a reasonably economical, nice thing to use. No reason not to, really -- unless using GH or IGF-1 at the same time, in which case the GHRP-6 will likely do little or nothing. But it does not sound as if that is your situation.
