I'm opposite. I can't really be bothered to use my AP for gauges, and the few times I tried the 0-60 and 1/4mi they were way off. And it's well documented that they're way off because they go based on wheel speed sensors but it takes a few tenths of a second for the computer to realize you've started moving. The vdyno is also a toss-up for me because no matter how hard I try, I can't get a vdyno to produce numbers anywhere close to something realistic.
I don't even do custom tunes anymore. To be fair I only tried it once with Mountune and I was less than impressed. I'm perfectly content with the OTS tunes from Stratified. I don't mind that they may be conservative because in the hot summer months down here, I'll be glad that my tune is conservative. With that said, the Stratified OTS tune can't be that conservative because it's heaps better than the Cobb and even Mountune, but I'm still only getting +3 ignition corrections occasionally, with no negative corrections, and no knock. AFRs are on point as well.
I monitor my gauges for a bit and do a few pulls when I switch to a new tune, then put the AP in the glovebox. It only comes out so I can get the numeric reading for fuel remaining so I can calculate how much cornjuice to feed it.