What BEC to use for MMP 1S version?

[snellemin]

The genx doesn't need one with the 2s A123. pointless really.
If the voltage goes too low, the dm bec just passes the lower voltage through. I do however use the park bec in my nomadio rx. I use a 2s lithium ion pack and need 5V max for the RX. Been working great for a while now.