[BrianG]

The case really does not enough thermal mass to shed the heat it produces IMO. Adding extra thermal mass and surface area does wonders to control the heat. Plus, the flat bottom makes it easy to add whatever heatsink that will work for whatever mounting you plan to use.

Another issue with the Quarks is the thick thermal sticky pad they use to attach the FETs to the heatsink. This pad doesn't move heat as well as thermal epoxy and tend to build up. You can take the ESC apart, remove the pad, and use thermal epoxy instead, but it will most likely void the warranty. However, I've done this mod and added extra heatsinking to both of my Quarks and they run a LOT cooler, even without any fans.

There are two other issues to consider:

1) They don't run 6s despite their rating, so you are limited to 5s or 16 cells.

2) Reverse brake is not quite right. When moving forwards, the brake is proportional. But in reverse, the brake is a sudden stop. Of course this is a non-issue if running in forward only mode.

Other than that, the Quarks run silky smooth and just about any motor. And warranty work is fast and easy from all reports.