Lol at the automatic poll option. I always leave it in neutral with parking brake on. Winter time I leave it in gear only for overnight parking just in case so the cable doesn’t freeze up.
I’ll put it in gear only if I’m on a hill or if I suspect the parking brake is not holding well
I always assumed it would be bad news for the drive train if someone smacks my car while in gear, but that is probably not the case. I assume the tires will slip before anything bad happens, or if the car is hit hard enough, it will be totaled anyway.
I only use parking brake unless I am on a hill either way.
Really surprised how many parking brake only people we have. Those of you saying, “only on a hill” realize how little incline it takes to get a car rolling right? This guy’s driveway looked pretty flat too, but his car still made it into the street. It was funny because nothing happened but with traffic and kids playing all around it’s pretty serious.
I stopped trusting the parking brake after I had to adjust mine on the GTO. When it was out of adjustment it would hold strong going forward (kill the engine strong), but the car would roll easily backwards. I set it on the slight slope of the parking lot at work (just drainage slope) and felt it grab as I was going forward. As I was getting out of the car I noticed it was ever so slowly starting to roll back. After adjusting it the thing holds great in both directions but from then on I always left it in gear.
I would think that it would turn over the engine, rather than do drive train damage…Which is why my gear choice dependant on hill direction…I’m always worried that if the car rolls backwards somehow, it will jump the timing belt or something.
I leave the car in neutral every night in the garage and push it out in the morning.
On level ground I usually will just leave it in gear.
Any kind of grade and I use the parking brake / in gear combo.
For 2009+ they put an eletronic parking brake on the CTS-V. Definitely something to get used to.
Im parking brake only b/c both of our cars are standards and have autostart (without any interlock). Its too hard to change habits every winter / summer.
Dan
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I did have this backfire on me once, years ago, in my old winter beater cavy.
I parked at the top of a huge hill at a friends body shop and apparently didnt set the brake quite hard enough. I came out like 30 mins later and my car was no where in sight. I always left the keys in it so they could move it if needed and assumed they had put it up back or something. Wrong. It had rolled down their driveway (prob a 30deg incline and at least 6-8 cars long) across the road, down a hill on the other side, between two trees and finally stopped with the rear bumper in a small creek. Thankfully, they also did towing, lol. Only damage was to the catback.
Luckily no one was hurt and I got a “fun” story to tell my grandkids someday
Dan
The majority of the time it’s sufficient unless your parking brake is seriously worn. My car is parked on a hill right now actually and only the brake is engaged 
I actually train people at work not to leave the car in gear. Obviously valet is a different case than day-to-day use of a vehicle you own, but for our purposes it’s actually much safer.
Also when I’m parked on a hill in my (automatic) truck I first pull the parking brake before putting it in ‘P.’ I don’t know it it makes any sense to do, but I’d rather put the bulk of the weight / stress on the parking brake instead of the transmission.
In gear and parking brake, always. You aren’t exactly stressing the car by leaving it in gear, you guys do realize you put like 10x the force on your gearset/bearings when you’re driving it? Although I am guilty of setting the parking brake tightly when I’m on a hill so the “stress” doesn’t hit the gearset. 
BTDT… On my hilly driveway at my old house. Good thing the ditch across the street stopped the car from rolling into the ravine. lol I now leave it in gear even on slight hills.
Hopefully Frost will see this thread…
Back in the day when he had a Jetta we worked out at Hamburg beach. His Jetta was parked in the upper parking lot, the one maybe 30 feet above the beach. Well needless to say we noticed his car through the window of the gym as the back tires were about to roll off the pavement and off the cliff. Luckily he made it to the car before it fell off. LoL
I tend to leave the car in gear with the parking on.
Parking brake and neutral for me. The neutral safety switch in my DSM is unhooked so I can reach in and start it.
For my DD, parking brake holds fine and if someone in my family (the automatic drivers mostly) decide to start it and jump out for whatever reason without taking it out of gear, they won’t wreck the car(s) or kill themselves.
Parking brake and in 1st gear (or in reverse depending on the direction of the car on a hill). I have seen a few cars with parking brake off and in gear roll away (and vise versa)
Always
I make my gf park her automatic car with the parking brake on bc we live on a hill. The noise that tranny makes when she puts it in gear after its been parked is horrible! I’ve trained her to stop, pull up the e brake while it is in drive (completely stopped, foot still on the brake) then put it in park. That extra strain can not be good
Always put it in gear, and sometimes also use the parking brake. Especially on customer cars, I never touch the parking brake, just leave it in gear. Too many sticking parking brakes around here. My personal car usually gets both every time though.
I parked my car today with both.
Maybe on a Honda 
If it’s flat enough that the car doesn’t roll in neutral with the brake off, I’ll just use the brake. Otherwise it’s always in first or reverse.
In my talon i would leave it in neutral and just use the brake because i had a turbo timer (although i could just manually shut it off)
This actually happened to me in my integra once lol. My car had a super weak brake, and i forgot to put it in gear. (my driveway has a really small slope) Well i went in after work to take a shower and my mom comes running upstairs and is like “omggg ur car is in the middle of the street!!!” … there was literally like 10 cars backed up and i live on a small side street lol. So i told her to grab the keys and move it , it had an after market heavy duty clutch so she stalled it like 16 times in a row lol. Luckily my neighbor down the street (neon9787) saw what was going on and moveed it for me lol