Its all in what you want. I have a 3/4" plate and I generally use the kidney plate instead for andouille. The very best andouille I have made was hand cut, no grinding.
I use 46MM B&P hog casing vice middles, I like the end result much better. I normally get my casings from B&P and have yet to disappointed. Generally I buy casings once a year and they will usually last a year. I always get some small sheep, some 28/32MM and 46MM. That about covers my needs.
The most important thing about andouille is lots and lots of bloom time. And that andouille is about the cracked black vice the cayenne.
I know I have 5 or 2 Q-View threads making andouille on here. I am pretty happy with it.
Editt, I smoke with pecan & corn cob and I highly recommend a double smoke.