Well, I haven't seen or read much on the "Gamo Dynamax", however, from the photos it just appears to be a Sportsman HV, in a BSA tactical synthetic stock and re-badged as a Gamo. That's not necessarily a bad thing. The Sportsman HV is a superb rifle. Yes, it's loud. So is any other 30 + FPE PCP rifle without a shroud or other help. Based on what I have read, all the BSA PCP rifles are and will continue to be made at the BSA factory in Birmingham.
I'm somewhat amused that folks will belittle a rifle and decry its performance or reliability when they haven't even shot one, much less owned one. "Billy Bob said so, so it must be true.........."
btw, for what is worth, Gamo has owned BSA a lot longer than 7 years. From the BSA web site:
• 1986 BSA Guns liquidated, bought by Gamo and renamed BSA Guns (UK) Ltd