Harrison is absolutely correct with the reasoning of the downsides of traveling, but I still want to partially argument for the other side
I would argue that there is a significant price difference. I paid ~30 k for a two-level lumbar. Sure, adding the travel and hotels will increase the price, but can you get a two-level lumbar by a top-surgeon in US for less than 40 k$? Of course, if you have an insurance that covers the cost, then it is a different story.
I fully agree with the no legal tools. But then again, I would cross my fingers for not having to need it in the first place... You put your life in the hands of the surgeon and then the outcome is what it is. No reimbursement is going to ever make up for a botched surgery. I don't know how successful lawsuits against US surgeons have been, maybe someone with more insight can weigh in on that.
So in the end, I would say that there are many factors affecting the choice. In some cases staying in US is the best, in other cases Europe may actually have both cheaper and better chance of success, but really, it is very situational.