A 4" revolver will carry better. Its noticeable when you sit in a chair. You may never holster it but camping or at the club, 4" works best. I have not shot 4 and 6 anything side by side but I did shoot 5" and 7.5" (44 & 45)revolvers one day and did not see the expected improvement in aiming. The 5" felt like a better balance. I would got with the 4" for those reasons. That is sight unseen and unheld. For the $$$ would be nice to hold one.
But now to contradict myself. With that vent rib and just looking at the two pictures the 6" looks better. And maybe a rimfire is ligther than expected? This one looks heavy. My single six has a 6.5" bbl and I like shooting that. But, If I did it over I would go 5.5. I shoot the 22mag and think the extra bbl gives me more velocity. I dont care about 22LR velocity. Apples and grapefruit.
I want rubber grips on any centerfire but in 22, this would look really sharp vent rib, stainless and with some exotic wood. For a beauty contest with upgrades, I like 6. Finally if you plan to mount a red dot that spoils the whole idea of a handy 4". Again back to 6.