Furniture Maker here...
For furniture at least the mix usually goes 1/3, 1/3, 1/3 can substitute mineral spirits for the turpentine.
I would be hesitant to use an oil varnish
blend on either high traffic areas or areas with lots of uv exposure.. (Unless you REALLY stay on top of keeping it up)
Benefits are that its much easier to apply than varnish
only. Can be wiped on or brushed on and wiped in/off.
Drawbacks are durability in comparison to lets say a varnish over epoxy
Holds up nicely on furniture, but again careful with the uv exposure, its a killer to almost all finishes.
is keeping it clean, scuff sanding
with a high grit sandpaper or steel
wool, and reapplying.
In most instances, oil-varnish blends work
in much the same way and in much the same capacity as rub-in oils. They soak into the wood and provide a thin, natural-looking finish that’s easy to apply. They may have a bit more versatility in terms of sheen and color options. Durability of the finish is slightly better than pure oils (due to added resins), but is usually still inadequate for high-traffic, high-wear pieces.
Look into varnish over epoxy
(epoxyworks from west systems has a good article on this.) Lots more work
up front, but worth it in the long run. In my opinion at least.
For more info on finishing in general, look at the book "Flexner on Finishing."