The visitherm stealth is highly recomended. They were, from what I've read, bought by another company, and redesigned the heater making the stealth pro. The pro has the green off/red on light on the temp dial. These are the ones that have the recall. The one I have. The old visitherm stealths are great heaters.
Now from what I've read, the plastic composite material that they use for the stealth pro has had some issues with air pockets. Those air pockets are causing the heaters to explode. Not sure if that's the exact reason they were recalled, but apparently pretty common for heaters made after the first 6 months or so after they began making them.