Safe or not, it's not that simple!
Buyer beware when it comes to buying shoes online, and I do not rec. using PayPal. I got screwed, took 3 years for my credit. Avoid buying shoes, on sale that states: "Final Sale No returns."
I bought 2 pair of shoes, $700 worth @ Zappos, where they have free shipping & free returns. I am a 5 1/2, so I bought a size 6. Returned them. Ordered a 5, too small. I saved $700.
I went to Nordstrom's, they're having shoe sales. Found 2 shoes, both less than $300. Both were rated as 'best comfortable shoes for walking'. BTW: I wore one of the boots for 4 hours, and I didn't even do that much walking, mostly standing on the same spot . . . . and I was already limping. I took it back the following day!
My son bought a pair of Nike beach sandals. They didn't come in his size, so he bought the one larger. They weren't sold in stores! He was walking around sandals too big, only because he didn't want to pay for return shipping and re-stocking fees.
Try different sizes. Not all size-8 shoes fit the same, even from one designer.
Walk on an uncarpeted surface. This is the only way to test how shoes will feel when pounding the pavement. Shoes that are good for some, may hurt your feet. Just saying!