Shimano FC105-5800 left side crank compatibility with Shimano GRX installed on bike


I have read through many useful forums on here explaining cranks and cranksets. I have found a 4iii left crank power meter FC105-5800 170mm for $299. I would like to install it on my bike that currently uses Shimano GRX cranks (170mm). I am wondering if I can switch the left side crank out for the 105 version? Would you recommend this? Should I wait for GRX version of the leftside crank power meter? Likely at a higher price.

Any advice is much appreciated.

I use a 105 left crank with my grx crank. The stance width is different by 2.5 mm. So adding in some spacers on the pedal spindle is recommended to make everything balanced, although you probably wont feel 2.5 mm. I only have one 1 mm spacer on mine and its all fine.

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Awesome thanks for the response! Very helpful and good to know about the spacers on the pedal spindle if I run into any problems.