To be honest, I'd try t find a deal on a brand name like Astron. But between the two you posted, I would take the Pyramid. I've used them before, and they are analog using pass transistors. The other, I know nothing about, and the build looks cheesy, and it is probably a switching supply. If so, and designed for RC charging, it's probably dirty as hell, and it is most likely all you will hear on the receiver. Just my ha' penny.