I went with the hellcat lower and upper box and 4" tubing, I tested the hellcat filter vs K&N drop in panel filter, there was a clear increase in air flow charge and mass air flow reading in my data logging, so I put the hellcat filter on the shelf.
I only use my car for street use. This set up works fine, and offers lower air intake temps than stock set up. Just what I was after, and didn't expect any more. Reasonable price and totally happy with it.