Thought I'd share my experiences. I have 2 pair of work boots, summer and winter.
Light and heavy. Brands? Depends what's on the shelf. Look for real leather and
Vibram soles. Personal preference. Red Wing makes good stuff, but it comes dear.
Go for sewn-on soles instead of glued if you can.
Gore-Tex breathes, leather doesn't. Much.
Waterproofing? Mink oil or neatsfoot oil work well. Wear the boots dry for
a couple of days, oil the stitching and seams lightly, wear another day,
oil the rest, wear 2 or 3 more days, clean frequently, re-oil every 6-8 weeks or so.
Words of caution: if your soles are glued on rather than sewn, by careful with pure
"brush-on" silicone or some brands of mink oil which contain a little bit of silicone.
Silicone will dissolve and eat glue. Seen it happen. Been there. Walked a couple of
miles back to camp once in my bare feet. Uphill. Both ways. :-D No fun. BTDTGTTS!
For snowproofing, there's a wonderful beeswax product in a blue and white can
called "Sno-Seal". It's also called "Imper" if the can happens to be facing the
other way on the shelf. Tedious to apply, but works its ass off. One or two
applications a winter will keep your toesies warm and dry.
I was just fourteen years of age when a coward by the name of Tom Cheney shot my
father down and robbed him of his life and his horse and two California gold pieces
that he carried in his trouser band.
Just seeing if you were paying attention.
Wayne/Campbell/Darby: Good.
Bridges/Damon/Steinfeld: Better.
The book by Charles Portis, 1968: Best!
Anyway, back to boots. Light applications of whatever you choose, about once a month.
Caveat: I've heard that libraries stopped using neatsfoot when it was found that
it cracked leather book covers after 50-60 years or so. If your boots (and you) last
that long, God Bless Ya!
Caveat 2: some places will tell you to heat up your boots before applying waterproofing.
Be afraid. Be very afraid. You'll overly dry the leather, and if there are any synthetics
there, they will crack and disintegrate over time.
Caveat 3: Don't apply anything to Gore-Tex, it's already waterproof. If you waterproof
it your feet will sweat like Aunt Jenkins' decolletage when cousin Jasper comes to visit.
Socks? 2 pair. Cotton dress socks inside and wool or wool/cotton hiking
socks on the outside. Draws out moisture like a madman and prevents friction blisters.
Caveat 4: If you're averse to applying any of these products to your new expensive
boots you probably ought to ask your valet or nanny what to do and maybe call Dr. Phil for a
second opinion.

Trust me.
Edit: Caveat 5: If you want to preserve the
suede finish on your new boots, don't apply
anything to them. Just buy a new pair if they get wet and Carlos won't let you in to Spago's anymore.