Any issues with this post-GentleWave retreatment?

[Annino1219]

Pre-op:

 

[MattKW]

From the low-res standard 2D Xrays you're showing, it appears to be a good job at endodontist level. If you're having problems, perhaps a cone beam might show something different. And some things can't be seen on Xrays, like cracks. If you're asking about GentleWave, then there is no system that is especially better than another, it really comes down to the operator skill.