While I really like my Zencar and like Alozzy got a great deal by ordering directly from China, Juicebox does make an excellent EVSE and for those that care it's UL listed with all the GFCI circuits. While I could have ordered my Zencar with GFCI they suggested not doing it to avoid false trips using in in portable situations, I agreed and haven't ever had a problem.
While the Zencar lets you adjust the maximum current, it only had a few settings. Mine has 3 while I believe Alozzy ordered 4? settings on his, Juicebox lets you adjust the current in 1a increments which is kind of nice. Whats not so nice(IMO) is with the Juicebox you need to use your cellphone and a App to adjust the current, no WiFi, no adjustment
To adjust the Zencar I simply need to shake
the EVSE within the first 30 seconds and before it starts charging to change current setting, KISS.
I believe all Juicebox's plug in, personally the way I'd want to go but if you must have yours hardwired you'll probably have to look elsewhere than JB or Zencar.
The VersiCharge is OK, I don't believe it has anyway to limit charging current but in your case that might be OK, cord lenght is OK,
not as short as some but shorter than the JB or how you can get the Zencar configured.
If you go with a plug-in style, the RV plug 14-50 is most common and can handle up to 50amps.