I haven't even seen a Soucy Extra, but I will say that I was impressed enough with the Cap-x that I bought a second one. I just finished the first and will fly it today. I haven't decieded what I'm going to put in the second yet! Just a note, I was able to balance the Cap with a BME 50 with no extra weight added, the reciever is mounted behind the rudder servo and the 6v batt. is back by the elev. servos. I'll try to get back later today to post on flight performance.