I started with the 64GB 10.5 iPP - once I loaded all the apps and started viewing and editing photos, I realized it wasn’t large enough. Luckily, there is a return policy and so I ponied up the $100 (plus tax) and haven’t turned back.
Got the 10.5 64gb and that’s more than enough for me, i dont store videos or games, photos are saved on the cloud but i do stream videos and music which dont use space at all. I dont use it to do productive work, its more a media consumption device for me. But multitasking on ios 11 is fun and makes me use the ipad even more like a laptop than a traditional tablet.