Your oil consumption doesn't sound out of line....to me. The oil consumption is a hit or miss thing in our VX's as some burn a LOT of oil and others don't burn any. My original engine burned 3/4 of a quart of oil every 350 miles (give or take). It did that from the day I bought it with 35,000 miles on it all the way until the day I had to have the engine replaced at 140,000 miles. Just to be clear, I had to replace my engine due to a burnt valve in cylinder three, not because it ran out of oil.
The standing theory is that the original engines had inadequate and/or too few oil drain back holes in the ring lands. Since the oil can't drain back into the case, through the drain back holes, it gets burned up during combustion and blown out the tail pipe. Since it really isn't burning a lot of oil at once there usually isn't the tell tale white/blue smoke. Isuzu actually corrected this on the later versions of our engines by drilling more/larger drain back holes in the ring lands eliminating the oil burning issue. It sounds like the reman engine that you have didn't have the new piston's installed so it still has the oil burning issue.
As long as you keep an eye on your oil consumption you should be just fine. Most of us check our oil at every fill up and top it off as needed.
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong, it usually turns out to be impossible to get at or repair."
-Douglas Adams, Mostly Harmless