Do you have in-house SMD assembly experience? When I was doing fast turnaround prototyping, being able to build up the boards in house was invaluable.
Do you need your prototypes to be on flex PCBs? If you can get the electronics ironed out on FR4 you're going to save a lot of time and money on prototype revisions.
If you're waiting for JLCPCB to assemble all your boards for you you're slowing your process way down. Pay for 2-3 day processing at PCBWay and then assemble in-house. If you can prototype on FR4, PCBWay can literally manufacture the boards overnight and DHL them to you before noon the next day.
Do you need your prototypes to be on flex PCBs? If you can get the electronics ironed out on FR4 you're going to save a lot of time and money on prototype revisions.
If you're waiting for JLCPCB to assemble all your boards for you you're slowing your process way down. Pay for 2-3 day processing at PCBWay and then assemble in-house. If you can prototype on FR4, PCBWay can literally manufacture the boards overnight and DHL them to you before noon the next day.