How long do you plan on being in the house?
Definitely take a look at the hardwood layer on the engineered, and compare it to the layer in the solid wood. If you get the thinner stuff, especially the 3/8" from Lumber Liquidators, note that you won't even be able to sand down to the tounge and grove joint. Often times, if you buy a nice engineered wood with a thick top layer, it will be equal to the thinner solid stock.
Just something to think about. It's not like you will be sanding this every few years. I'd guess 15-20 years is more like it.