SR20 main bearing housing oil grooves

Does anyone have any experience with putting oil grooves in the main bearing housings of SR20s?

I'm getting ready to send out the block for machining and I'm wondering if its necessary or if using grooved bearings will achieve the same result?

I attached a couple of pics showing the type of groove on the main bearing housing.

It depends what bearings you want to run. The generally accepted 'best practice' for a high power SR is to use the GTiR main bearings which then require the block to be grooved in order for the bearings to work properly. For a mild build there's nothing wrong with just using conventional SR20 bearing shells which don't require the block modification.