I have both the .22 and .25 streamline and I will say the .25 with a moderator seems a bit too long for me. I stil use it of course at times, but the .22 streamline is just my favorite that I always go to. Now as for killing power I am always a little confused with the head shot vs body shot argument. The first shot that starts to be less effective in my opinion is the head shot, and I say this from a lot of experience. But skulls are a stronger thicker bone and with our lower powered guns at ranges it can be harder to penetrate that bone, so what we end up doing is giving the animal a severe concussion and a nasty wound but they can still survive it. However the chest although doesn't give the same lights out effect is much easier to penetrate and almost always kills the animal within a few seconds after the impact of the pellet. And if going for chest shots the larger the hole you can tear the faster they will bleed out and expire, but a .22 with a expanding hollowpoint is just as effective as a .25 round nose. And the .22 hollow points open up better at further ranges than the .25's will, probably due to the extra mass of the pellet in a .25 giving it more strength. However the .25 hollow points can be very lethal when they are opening up.
One other thing I would like to add is know the anatomy of the animals skull thickness when shooting. I hear people talking about needing a bigger more powerful gun for fox over a skunk or ground hog, But really those little fox are so fragile that they don't take much to penetrate their skulls(I shot clean through one at 176 yds with my 22 streamline). Groundhogs and rockchucks actually have pretty tough little skulls for their size(I won't head shoot them past 75yds with the .22). Skunks a little stonger than a fox as well. Just a few thoughts
By the way the streamlines both shoot the H&N barracuda hunters well out to 100yds. Beyond that I stick with the JSB's to make sure of better shot placement, although they will throw the hollowpoint well winds can grab a hollowpoint and pull it off course pretty easy.
