On OEM parts, I ususally will order with my PC... and open a tab for each parts vendor..
RockyMountain ATV/ProCaliber/RonAyers/Partzilla...
I'll set up my order on each site... then the one with the lowest cost and parts available get the order.
Much of the time, the winner is RonAyers.

I've done the same many times and the deference is not great when taking into consideration min order for free shipping. At least that's what I remember.
Rocky mt atv seemed to have everything in stock and with 2 warehouses, the orders were filled, shipped and received quicker.
Just my experience.
Most suppliers seem to do good.