If the wood is relatively even in grain pattern, short board lengths aren't all that noticeable. The problem is if you get lower quality wood with lots of character as the joints will be quite noticeable. I don't think you will find many boards longer than 6 or 7 feet, even if they describe the product as lengths to 10 feet. If you see bundles of unfinished flooring, the bundles usually are more like 8 feet and very few boards are full length.

My friend who is an experienced installer has had bad experiences with product from Lumber Liquidators...missing tongues, split tongues, cracked boards, slight width differences... The problem with low quality wood is that you end up buying more square footage than usual to make up for the unusable portion so you don't save money in the long run,

This is an area I would advise a client not to skimp on. There are a lot of horror stories with Lumber Liquidators as Linda has mentioned. When suppliers consolidate products that are made at different times and sometimes at different locations, the worst thing to deal with are the slight differences in thickness of the boards which cannot be worked out in the installation process. There can also be noticeable differences in the finish and graining of the boards.

If you can, it would be cheaper to install unfinished and have it finished on-site. Then you have consistency and someone to go to if there are issues.

lowes has good choices,stands by products,diff price points.
lots of USA products