I wanted to hopefully provide what I believe to be a valuable resource for folks who are looking for the perfect fit (all puns intended) when it comes to a thru hiking shoe or boot.
Let me first start by saying that whiteblaze.net has been a huge resource to my wife & I as we've planned and dreamed about our upcoming thru via this website since 2005. I thank everyone who has ever posted here, it has truly been an inspiration and blessing!
From what I've read of most every account of a thru-hikers experience with footwear via books and accounts via web, I have noticed that a thru-hiker is most likely to end up switching footwear out early in the hike, becuase the footwear just wasn't working once they got into the day to day rigours of hiking. I don't know if this is somewhat because of not thouroughly trying the shoe out before hitting the trail for six months, but there is something I suspect is true in most cases...individuals go with footwear that is a "close fit" but not the "right fit". And I believe in a lot of cases this is because of most shoe stores' return policy. If you go out and buy a $120.00 pair of shoes and the store won't take them back after a long hike, you are likely to think that "these shoes" or "these boots" will work fine. That rubbing will work itself out. Etc.
Let me also say that I don't believe in a perfect fit for anyone...unless you have someone make you footwear tailored to your individual feet. But there is a "right fit" out there for most everyone. It exists. Don't give up hope!
My wife and I have both gone through 3 and 4 different shoe styles and brands before finding what we believe to be the "right fit" for our upcoming thru hike, and it's due to one thing: A store like REI. I would highly recommend doing your shoe shopping from this store or another who offers no hassle no questions ask 100% satisifaction. It will ensure you can test the footwear out on the trail. Case in point: the last pair I took back was after 12 miles and they looked like a pair of shoes no retailer in their right mind would take back. The shoes were rubbing and slipping a bit, something I didn't notice at first in walks around town on pavement. The clerk looked at them, and said I hope we can find something that works for you this time.
We went to one retailer who told us try the shoes out in your living room, just don't wear them outside and you can bring them back. Another said try them out, just keep them on pavement and if u want to return them bring them back within 7 days. Pavement and living room floors are not going to tell you how footwear will perform.
I hope this helps some folks in deciding on footwear...I have no personal interest in REI besides general membership and in fact there may be other stores out there that do the same guarantee. I believe it would be in your best interest to drive to a store with this policy so you don't end up spending big money on footwear you need to trade in fifty miles down the trail. You may also be able to work with a store like this through mail order...the gas money you spend to go to a store like this or the return postage it may take you on several footwear attempts will be far cheaper in my opinion than buying shoes that you can't thoroughly test out.
Please understand I'm not a footwear expert, and in fact my wife and I still may face the reality of trying to find a new footwear only a few miles down the trail because of an oversight in our footwear selection...but finding a retailer who will work with you on such an epic undertaking as a thru-hike should minimize this possiblity.