I used 175's on my MTB, and 172.5's on my road bikes for years. Then I realized my cadence was insanely high all the time on the road, so I decided to try 175's, slowed my cadence to around 110, gave me more torque when out of the saddle, and felt better all around. According to most calculator's I should be on 172.5's but I can't STAND riding cranks that short anymore. Most don't seem to notice a difference, to me it is huge.

I would at least say it can't hurt to try a different size out and see if you notice a difference, you may prefer shorter cranks.