I own both, and think they have the best 2560 x 1600, fully laminated panels in their respective sizes and in the budget (<USD 300) price range. I no longer buy Full HD devices. If you want to move a >32GB uSD card among devices, don’t get the Hi9 (supports only FAT file system). Otherwise, it’s what size you prefer. The 8″ fits in cargo pants pockets, so it’s EDC, esp. on mass transit, reading or surfing if someone else is driving. I like the 5″ size of phones… easier one-handed ops but not optimal for docs and reading. I use the T10 for longer period sessions … planes, airport lounges. Sometimes when when away from the office and in a conf call with clients, I have my phone (Pixel on Project Fi), Hi9, and T10 all out and active. Hi9 has the conf call agenda, T10 has the document under review, and taking notes on the phone. I highly recommend Project Fi if you use mutliple devices… 9 data SIMs, no extra charge, one data bucket.
Alternatively, you could spend 3x to 10x as much for the Huawei M5 Mediapad, available in 8.4″ and 10.8″, and gain real USB-C, 256GB uSD support, and 4G (17 LTE bands, 200 countries). https://www.anandtech.com/show/12476/mwc-2018-huawei-press-event-live-blog-1pm-utc-8am-et For that price point, I would buy a notebook.
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