I've been using the HAx1 since I got my juki 2010 a few years ago. Have not had any problems using them, and I sew a lot. Normally when you are piecing, it's hard to get really going fast for any length of time. The heavy duty needles might be more appropriate for FMQ if you really like to zip along.
I don't consider the Juki to be beefy. It's mechanical, but not heavy duty or high speed compared to industrial machines.