I'm not on that setup anymore, no, but no cons, really. I was happy with it other than it being too slow for me.
My build thread is linked in my signature.
While this is true, OP said he's going with a GTP unlock, which means you can't use most of the stuff, no flex, no anti-lag, no map-switching, etc. With a GTP/Femto unlock, you only get access to calibration tables so it's about the same feature set.
If you do any sort of dig racing, you're gonna need axles and a decent tire. The build is fine, you'll hit the 750/650 goal no problem. Have you decided on a tuner yet?