I actually have bought a pair of shoes from that website. Few things: First if you do order, make sure you are getting the correct size because they dont go by american standard size..they do have a size chart comparison that is easy to read so you make sure you get the correct size when ordering. Shipping was free for me I believe and arrived quickly with a tracking number, so no worries about ordering from this site.
On to the shoes themselves..
They claim to add 5.5", but I dont think it is actually that dramatic. You, and everyone else also, will notice a drastic distance in height but Im not sure it is 5.5. I will have to measure myself again with these on and report back. Im used to wearing boots so they did not feel that heavy on me. Walking in them was no problem for me, though I have yet to walk in them while in full costume (since Im still building it). The only thing is since the height is much different, I recommend using handrails on stairs since your center of gravity feels off and you may loose your balance easier on stairs. Regular flat ground should be no problem, I put them on and walked fine right away.
I will say this though, the picture is misleading. It does resemble what is pictured but it's not exact. The boots I ordered looked like the one pictured above (it may even be the exact pair) except the ones I recieved had a gloss finish, the laces seem more like that of a sneaker and not the rounded laces of a boot, the stitching is all black - not white like pictured.
Since most of us Im assuming are covering them with their armor anyway, it doesnt really matter much about the appearance so it wasn't an issue for me.
Also, I just checked their website from the link provided above and it seems like they are much more than I paid (from the same website). They do have special offers, so maybe I bought them when they were cheaper but I remember paying about $85 for mine.
Im not knocking, their product or promoting it.. just wanted to give everyone my opinion since I have a pair from this website. They do what it claims - adds height, and if you're standing roughly 5'7" without armor then they do help give that larger appearance when adding in your undersuit and armor and padding. I wish I had mine done so you can see with and without pictures as to what kind of effect they give. Im my opinion $80 for a pair of boots you may buy anyway, these are worth it.. for the $160 or so I saw briefly looking on the website just now.. I'd wait until they were in the special offer catagory again. hope this helps guys! (and gals!)