My merv blew its stock esc a few weeks ago so i opted to upgrade, i went for the Castle SV3, i didnt realise that the new ones dont have hard wired motor wires anymore, they have 4mm bullets.
I had the bullets but not the space to do the usual sideways mount that most folk do when they do this conversion as it would stick out through the body shell.
Instead i opted to swap the esc and rx around and get busy with the dremel, i am pretty happy with the results. The battery tray under the new esc is now for the wires and switch as i wanted these out of view, i wanted the install to be as clean as possible without sinking the esc into the chassis which i hate the look of.
I ran a 2s pack through her tonight, neither the esc or motor got hot, barely warm infact. this upgrade is great, the sv3 is also punchier than the stock traxxas esc with the bonus of being compatible with the castle link, i had to tame the brakes as it would flip over under the sharp braking. i didnt realise the velineon motor had so much more to give.
Anyone tempted to do this i can highly recommend the upgrade.