The 1410 isn't smaller in diameter than the Medusa, at least not by a noticable amount
I was looking at the Castle website and it stated the 1410 is longer than the 36mm motors but the diameter is 25mm where as the Medusa is 36mm. But the thing that caught my attention was the fact they(Castle) said it was an improvement over the already excellent 36mm motors.
CF Ofna GTP II Extended Chassis Castle/Flux 2200kv 6s
CF Ofna DM-1 Pro CC1717
CF Sportswerks Mayhem ST
CF Losi LST2