Mike, do some searches here for answers to some of your Jet vs. Griz question. Before I bought my Griz G0632 I did a lot of research on the two. There were no big surprises regarding differences and a couple areas still remain unclear.
I concluded that the two are, essentially, the same machine. I think Jet does offer a 220V option.
The warranty is a big consideration, I'll grant that. But, there is a Griz store within reasonable distance of where I live. My son lives near there also so a trip up is not a chore for me. I can pick up new tools and save shipping.
BTW, I am very happy with mine, it is a great lathe. These two are 90% of what one buys in brands costing thousands more.
A tip: If you buy either one, have help assembling. Especially when it comes to lifting the head. It is very-very heavy and would be (literally) a hernia buster if one tried to lift alone.
"Folks is funny critters."
Think for yourselves and let others enjoy the privilege to do so, too. ~Voltaire