Yes, my girlfriend is doing this, but not in a way you would like. My girlfriend is the primary user of the MPW. I am technical support.
Basically, at the moment she plugs SD cards into the MPW and hits the Wi-Fi button to download her photos to the MPW. As she uses a Nikon camera with two SD card slots, she saves JPEG files to one SD card, and NEF (RAW) files to the other card. Both cards get backed up to the MPW. This is considered the on location backup for her photos. Often she will continue to shoot on the same SD cards without deleting the photos already downloaded, and then will download again later. Only the new files are downloaded at the later time.
However, if she wishes to review the photos, perhaps tweak a few and upload them to social media or somewhere, she tends to also copy the JPEG SD card to her iPad using an Apple SD card reader, and then use Photo or iPhoto to do what she likes. It is duplication of effort, but it is actually easier and quicker for her to do that. This often causes memory availability problems on the iPad, but she tends to delete all the photos she isn’t going to play with, knowing there is a backup on the MPW, and just keeps a few photos on the iPad. It is a shame that iOS requires the photos to be copied to the iPad before they can be used, rather than just browsing and opening the photos directly fro the SD card.
Anyway, she is aware that the My Cloud App allows her to browse the files copied to the MPW, and she does use that a bit, and intends to use it more. But wanting to use iPhoto for edits is the stumbling block, as the photos need to be in the Camera Roll or an Album for iPhoto to access them.
I have had a look at “FileBrowser Lite” which does some good stuff, but still isn’t a solution. I haven’t bought the full version yet to see if it meets her needs better.
However the “My Cloud” and “Photoshop Express” Apps combined can provide a workaround it get photos from the MPW to the Camera Roll in iOS. So far she hasn’t got into using that workaround though. My workaround is described here: http://community.wd.com/t5/WD-My-Cloud-Mobile-Apps/Cannot-download-photos-movies-to-iPad-using-app/m-p/843293#M5412
PS: Increasing the cache used in the My Cloud App may help with your original problem of buffering when when scrolling through images. The cache is set by tapping the Menu icon (top left of screen in home page), tap Settings, and check the Cache Size setting. Try a larger cache and see if the buffering improves.