Thanks JC!
I was being a but lazy, but also a bit hare-brained. Didn't know where to look for the answers in the FCOM.
I wasn't looking for advice on how to fly the SID, but really asking about the aircraft behavior, and you really nailed it for me!
So, as I understand it, if you enter a pre-selected speed on the PERF CLB page, that's exactly what she will fly, regardless of green dot, or flap position. (with all other protections still applicable, e.g. VLS, auto flap retract, etc)
AND, if you leave everything managed, it will go to a) 250kts if there are no other constraints, or b) either GD or the SID constraint speed, whichever is higher.
Thanks for your help.