General silencer discussion. If you want to talk about a specific silenced rifle or pistol, it is best to do that in the rifle or pistol section for that brand.
Yes. It is ok. The M4-1000 is more durable than any silencers from any other maker that I know of. Only more expensive models from AAC are more durable.
I know of no suppressor more durable than an M4-2000 Mod 07. So if you wanted to suppress a 7 inch, none would be better. However, AAC does not guarantee a warranty on 7 inches. Yes, it suppresses. I have posted many Beta mag videos of AAC cans on 7 inches.