liuzengqiang:
Great! Thanks guys. I'll make a decision soon. My other goal is to power a raspberry pi with it besides MCU so there needs to be just a single power source. I was hoping to get something that supplies 2.xA at 5.1V. Maybe the murata module will do just fine.
Perhaps OKR-T/3-W12-C from Murata fits your purpose... input voltage is 4.5-14 VDC. Output is up to 3 Amps with great efficiency at 2 Amps. One external component, a resistor, programs the output voltage. Fits nicely in .1" spaced holes. And, the price isn't too bad for what you want.