Mid length is going to be easier on the components as well. Port pressure is much lower. It also corrects the problems that led to the carbine gas guns needing extractor o-rings, H buffers and so on. Only way I'd buy a 16 inch carbine gas gun these days is if it said Colt or was a smoking deal.
That rifle gas 16 inch dissipator in the above pic would be a no go.
That rifle gas 16 inch dissipator in the above pic would be a no go.