Just got these in. They look just like the picture with the D-SUN branding in the corner. I was curious about the inrush transient other people had been mentioning. After looking at the units under an oscilloscope, I've actually observed the issue on powering OFF rather than powering on. I've also noted the transient doesn't happen when powered from a battery. I've a theory to that as well. To make things clear I've attached some images for reference. Testing constraints: - Converter output set at about 5 volts DC. - No load on output except oscilloscope. - Testing with 9VDC battery as well as benchtop linear power supply. Image 1 shows the output of the converter on startup. It ramped up to the set voltage without any overshoot. This images is reflective of the observed results of both the battery and the power supply. The power supply was tested on ranges from 12-24VDC and all with a similar look. Image 2 shows the output of the converter when the linear power supply was shutdown (power to the liner power supply cut). Before output drops to zero, it experiences a spike along it's ramp down. Note that the spike is exceeding the set voltage by over an entire volt. Image 3 shows the output of the converter when disconnected from the 9 volt battery. This is what most people would expect for output shutdown. So why the spike in voltage when powered from the power supply? I suspect image 4 may help answer that question. Image 4 shows the output of the converter when the linear power supply is set to 7VDC (about 2 volts over converter output setting). Output suddenly becomes unstable. Probably because it doesn't have enough overhead. Notice how the voltage is spiking to a similar level as before. Here is my guess to what is happening. I believe since my linear power supply has some sizable capacitors on its output, that the voltage is not falling instantly on shutdown. While it is dropping, this converter is still doing its thing and creating the set output voltage. However, as soon as the input voltage drops into the range where the converter doesn't have enough overhead, the converter freaks out and starts spiking. But for me at least, it only get's one spike off before input voltage is so low output finally becomes zero. This is probably why when powered from the battery there was no spike on shutdown-- the voltage from the battery was instantly removed. That being said, be very careful about maintaining overhead when running from a battery. If your voltage gets too low, you are going to be getting output spikes. If just to get through the shutdown phase, a larger filter capacitor can probably squelch the majority of this issue like others have noted. But just to be clear, I think most people will experience this as a shutdown issue, not a startup one. To be fair, though, I tested for start up spikes by raising my linear power supply slowly from zero to 9VDC and got voltage spikes that way as well. If you pass though the not-enough-overhead range you will get them every time. I think power supplies generally turn on faster than turn off though. Your results may be different. Regardless, go for fast on and fast off and things will be okay.