Update:
no sign of engine until today, july 3th, 5 months after payment!
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Got them on the phone several times in the last 3 weeks.
June 16th:
"yes, motor is being put on the dyno this moment, will be wrapped and shipped in 3 days at the latest"
June 23th:
"Motor is finished, has to be cleaned. Dyno video will be cut and link will be sent within 1 day, shipping in 2 days"
July 1st:
"Detected a leak in the motor, has to be sealed again...
Ready for shipping early coming week!"
There still is no link to the dyno-video as of today.
So build your own opinion of that company!