The MT 5402 in-house movement has a longer power reserve like three days compared to the ETA's which is about two days. This is a technically more advance movement and chronometer grade.
The ETA version is a more nostalgic design due to the rose logo and the smiley script.
I have a BB (burgundy bezel) and a BB58, both with Tudor's in-house movement. It is MT 5602 in the case of the BB.
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