I am a recent customer of ScanMyPhotos.com and want to share my experience.
TL;DR...I recommend them and would use them again.
I had hundreds of old photos scattered across many albums and boxes, so I decided to gather them up and have them scanned. I paid for 600dpi scanning, "Photo Soap" cleanup processing of scanned images, and a few dollars extra for a USB thumb drive of the images. There was a coupon on the website at the time of my order and I think the whole deal was around $160, which included shipping.
I was sent a USPS Priority Mail box to place the photos in, along with packing instructions. I read the instructions twice but still managed to get it wrong. I grouped photos according to size and I placed an index card at the front of each bundle to indicate the date of the following photos. Turns out that is not how they wanted them packaged and I had to pay extra for their "Scan In Order" service, but it was only $34 with 50% off so it wasn't too bad. I managed to get 880 photos in the box, most were 4x6. I had extra room in the box so I could have put more in there if needed.
I shipped the photos out on a Thursday and two weeks later my photos were returned to me along with a DVD and thumb drive with the images. (I may have gotten them back sooner if I didn't pack the photos wrong to begin with.) They packed the photos more carefully than I did! Scans are great, no issues found so far. Now I just have to pull them into Lightroom and start tagging.
Great customer service, great results, and I would use them again. I'm a happy customer!