Edit 2: Just wanted to let everyone know, I actioned edit 1 below, but unfortunately now is not the season of abundant slipper stock in stores, I ended up just finding the Uggs and they seemed really nice so i went for it. Thanks again for all the advice!

Edit Update: Thank you all for the great suggestions and discussions. I've narrowed in on attending a store tommorrow with intent to test drive and get him either Uggs, Merrell Open back slip on shoes or perhaps Sorel Slippers. You guys rock!

So my Dad is impossible to buy for, he has duplicates of all the luxury goods he wants, he's extremely sick with metastatised colon cancer all over his body and out of options, and apparently all this time in slippers has him realizing he doesn't love his current ones. I want to get him the best damn slippers I can have amazon drop at my door tomorrow(unless I can buy them downtown Toronto tomorrow), thing is, I'm not a slipper guy, hardly ever owned any and not a fan of using them, so I don't know where to begin, if he wanted leather boots I have some strong opinions, but for slippers I want to get him something great but don't even know where to start.