I used the spray that I have on my AEG hopup only when I first got it. I was told by one of my experienced airsoft friends it's a good idea to give the barrel a cleaning and give the hopup a tiny tiny little spray. And I'd only need to spray to hopup again if I was storing the gun for a long while.
I still use the spray to clean the barrel occasionally, just a tiny spray on the little cloth.
What I was mainly wondering about was lubrication for my GBBP.
It's good to know that the stuff in my link wouldn't be detrimental to my gun, however not as beneficial, and cost effective as the grease.(I wonder If that's the same grease my friend uses on his GBBR, I'll have to ask him.)
Either way. I appreciate all the advice. Just one more question:
When using the grease on my GBBP how often should I clean it off and re-apply? Or do I just use judgement with how dirty it looks?...I guess that was two questions