Can you test your link with iperf and tcp protocol?2 links with SXT, some of the traffic is generated with btest. Ping is very low, speed is good. I hope that 3x3 will be at least like this.
JRC-24-EXTREME, RB411AH, R5hN, Single Chain setup, 40Mhz, nv2, net. 98Mbps (Measured with two notebooks, with iperf).
add name=vpls1 remote-peer=172.16.0.1 vpls-id=1:2
add name=vpls2 remote-peer=172.16.1.1 vpls-id=2:2
add name=vpls3 remote-peer=172.16.2.1 vpls-id=3:2