Most consistent non first growth boardeax?

I would say that Ch. Talbot deserves consideration.

For sure. And the likes of Canon, Lanessan, Lagune (back in 2004), Carmes Haut Brion, etc.

What about Grand Puy Lacoste for consistency?

Great call!

The workman of the Classified Growths.

VCC hasn’t been mentioned.

Didn’t they change owners in the past ten years or so?

LLC but that’s 2nd Growth.

Since 2005, my pick would be d’Issan.

‘82 to ‘17, Lynch Bages,

I would add La Mission Haut Brion. I agree with many of the prior choices.

Based on the OP’s criteria, I would choose Lynch Bages, but I’ll put in a plug for Gloria in a lower price range. I’m drinking the 1981 and 2008 tonight. The older one is beautifully mature and the younger one bold and tannic, but you can see the resemblance.

for me…

leoville las cases
lynch bages
pichon llande
pichon baron

Croizet-Bages… consistently mediocre … !

Grand Puy Lacoste
Leoville Barton
Lynch Bages

I have a personal soft spot for Rauzan Segla, which has been very consistent for me on a handful of vintages since the mid-90s.

Cantemerle, DDC and Leoville-Barton

I was going to put Cantemerle down as well, and in the grand scheme it has certainly held the line, but starting with the 2005 vintage I think they amped the recipe up a tick. I’m still a fan though. Not sure if others have had the same experience.

Leoville Barton for sure though.

+1

John, you might want to check out my recent research on Left Bank Bordeaux. I think the rating I came up with is your go to list.
The Best Wines of the Left Bank of Bordeaux