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From my recent experience:

Fire HD 10 (gen 9) — perfectly usable, a cheap option. Meters are smooth one minute, then lagging the next, but you can use everything without issue, apart from the latency as it relates to visual feedback.

iPad Air on same Wifi — About 3 times better in terms of lag, overall latency (meters hit much tighter now). Occasional mini-lags as it negotiates WiFi, but nothing like Fire HD.

iPad Air with Ethernet adapter — Even better, no lag that I've experienced. Might as well be built-in. Comes at at obvious cost, but at least I have an iPad now, that I can use for other things when not working.