I gutted it down to the walls. Now I am putting in a new Dishwasher. What is best for DW discharge: stand pipe, or dump it into the garbage disposal? Forget about the local codes... Do you REALLY need an air gap? I can't be too important because some places don't require it> Please advise from personal experience only. Thanks.

I gutted it down to the walls. Now I am putting in a new Dishwasher. What is best for DW discharge: stand pipe, or dump it into the garbage disposal? Forget about the local codes... Do you REALLY need an air gap? I can't be too important because some places don't require it> Please advise from personal experience only. Thanks.

Hey! Ya want personal experience? How's over 50 years experience and hundreds of dishwasher installations grab you?
The easiest installation would be to route it into the disposal. To build a stand pipe you'll need to trap and vent it. The disposal's already trapped and vented so it's the easiest with less hassel.

Do you REALLY need an air gap? I can't be too important because some places don't require it>
ALL CODES REQUIRE A AIR GAPYou must install either a counter air gap or a high loop,(see images) on the dishwasher hose. To allow the hose to hang down would drain all the water out of the tub while attempting to fill. In my area we install high loops .as per against counter top air gaps. The reason being is that we get no service call backs with high loops. We can't say that about air gaps. But YOU MUST install one or the other. If local codes allow, you may forgo installing an air gap and install the drainage hose with a large loop between the point where it discharges from the dishwasher and enters the sink drain. Think of a bell-shaped curve. Make sure to attach the drain hose as far up in the cabinet as you can, using hose clamps or a pipe strap to secure it, when you run it between the dishwasher and the disposal.
Good luck, Tom

Not installing the air gap or high loop will also allow contaminated water to flow from the disposal or sink back into the dishwasher.