I used the Label Peelers #9 1-3/4" premium corks and they seemed to be of good quality. They are rated for 4-6 years of storage but they are definitely hard to insert, even with a floor corker.
Nowadays I use NomaCorks exclusively. They are rated at 10+ years of storage, I can store the bottles upright if I need to (no need to wet the cork on the inside) and they seem easier to insert. Plus when opening a bottle of wine I don't get the cork crumbs, as with natural corks. I don't care much about the extended micro oxidation once the wine is in the bottle. I would rather be at peace knowing that the wine is hermetically sealed in the bottle and decant every time I open one, than the alternative. There are pros and cons for each type of cork, but to me simplicity and peace of mind is key.