11XL would be my guess- 1600kv according to the spec on the trx website, 11XL is listed as ~1588kv on the feigao website. Seems like a good choice for 6s use though, keeping the total rpms at a reasonable level to avoid burning up the motor. Castle now have it listed at their 'low price' of $389, which is pretty darned good- wonder what it'll cost in UK shops... ( more like £389 as per usual
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