Ok lets try thinking about it this way. Your packing that 40 mid size anyway. six less rounds saves you a few grams of weight. Thats grams not pounds.
Now just food for thought here. Is your life or the life of your wife gf family etc worth a few grams of weight???
I see where your going. Why carry 6 more when a lot carry 5 in a Sp101 357? A lot like five for sure and dont trust semi auto. I carry semi autos and trust the ones I do so its not about semi vs revolver. I also carry a 357 mag at times with 5 and with that particular round im totally comfortable with 127 gr jhp.
But if im going to pack the mid size semi Im going to load it to capacity. Why?
For the same reason I would not load the 5 shot 357 with 3 rounds. If my wife or family was killed or injured because I only carried approx half the fire power available to save an ounce of weight I wouldnt sleep very well afterwards. Just something to think about.
edit I guess if i did that and got killed myself because of it Id be sleeping ok but waking up would be a little hard which would be a real bummer