I have mine drilled 5/64" in the center. If it makes an air noise, I don't hear it(music too loud
) Here is exactly how I installed mine(in idiots terms, since I am an idiot..lol):
Disconnected negative battery terminal
Loosened screw on metal tightening thing(for lack of proper word) around the hose
pulled hose loose on side that points to the passenger side
put drilled cap on my finger like a thimble and greased it
pushed it into the hose about an inch and a half
put hose back on and checked for proper fit
tightened screw on metal tightening thing(I really don't know what it is called
)
reconnected negative battery terminal
turned on headlight/fog lamps and Max A/C to HI
started car and let it idol for a few minutes(perfect time to reset lost settings caused by disconnecting the negative battery terminal)
shut car off
keeping lights on and Max A/C on HI, started car again and let it run for a few mins. After that I drive it around the block(with hood closed of course).
Shut car off
Moose is gone for good!
Now, this may not be the proper way to do it, but it has worked for me so far with no complaints. I always turn the headlights/fog lamps on and Max A/C to HI each time I disconnect/reconnect the battery.
As for the auto up/down feature, I don't have it(I don't think they offered it), but a few guys here have done it IIRC.
Last time I had low RPMs and a check engine light my IAC was replaced. 
. The only minore problem that i'm having is that when I turn on my ac, the rpms are between 500 and 750 when I have it off, it goes back up to 750. I'm so happy now. I just got done playing with it. I disconnected the battery for about 15 seconds and I put it back on and the check engine light is not on anymore. It probably cleared a code or something.