Nrf52840 SPIM3 Highspeed 32Mhz SPI...has anyone tried it in SDK15?

I have a display that I want to drive at 32Mhz via SPI. Reading around has found that it is under the SPIM3 on the nrf52840. I see the in TARGET_SDK15 there is new code (targets\TARGET_NORDIC\TARGET_NRF5x\TARGET_SDK_15_0\modules\nrfx\drivers\include\nrfx_spim.h) that appears to implement SPIM.

It can be enabled by modifying sdk_config.h to set NRFX_SPIM_ENABLED.
Only problem I see is that the spi_api.c (targets\TARGET_NORDIC\TARGET_NRF5x\TARGET_NRF52\spi_api.c) includes the nrfx_spi.h NOT the nrfx_spi.h.

Had anyone tried out the SPIM implementation on the nrf52840 yet, and if so is there some docs on how to enable?
I presume you must disable the NRFX_SPI_ENABLED which is currently enabled as I think they use the same hardware.
Any help is appreciated.