I think a lot of people have likely just never heard of an Echowell wireless computer. Usually my answer is "don't buy a wireless bike computer, just buy a wired one and have the shop install it - you don't risk getting weird and obvious false stats at the end of your ride, you don't have to replace the battery every few years, it just stay on your bike and works". If your folding bike folds in such a way that a wire won't work, I can understand that's a little different though.

Just don't have much experience with a wireless speedometer...