For those people who have trouble making a decision between RK2020, RGB10 and ZPG Pro, I will make a comparison in this video.

Dimension comparison:
RK2020: 14.3 x 6.5 x1.7cm
RGB10: 14.4 x 6.3 x 1.6cm
ZPG Pro: 15.1 x 6.6 x 1.7cm

RK2020
Pros:
unique shell
neat analog stick
reasonable shoulder buttons
high cost-effective

Cons:
fuzzy characters
rattling shoulder buttons

RGB10
pros:
additional custom buttons
high definition
lightweight

cons:
commonplace shell
low-profile shoulder buttons

ZPG Pro
pros:
good build quality
sleek edge corner
comfortable direction pad
abundant games preloaded
beautiful image

cons:
delaying and frame skipping in some games
unreasonable shoulder buttons
relatively expensive

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