It only took me about 2 days to learn, though I did use the dip switches so Delete is Backspace and the Alt and System keys are swapped since it felt like I had to do finger gymnastics to hit the Alt in its default position. Overall I really like this layout and I use my HHKB Pro Classic any time I'm working on something/chatting. The Ctrl position just feels so much more natural, I actually switched my other keyboards to have the Ctrl in that position haha. In games where you press Ctrl to crouch it feels way more comfortable and easy to reach, it's actually improved my movement quite a bit in FPS games!
Yeah, hhkb is amazing, till the time where I need to edit text and use arrows a lot - then its f***ing pain in the ass 
If your HHKB is a reprogrammable one or you have an aftermarket controller you can try swapping arrow keys on the second layer to WASD. I can't do it on mine because I have a Pro Classic but I do it on all my other keyboards that don't have dedicated arrows. That way you can just do FN + WASD for arrows.
I know, I've done it, but Still, my hhkb is in a cupboard, can't use it really.
You can program your Classic, I've done it with mine, when had one. Its a new trick with those new keyboards, you just have to edit your software file.