Sorry about the thread-drift, but it IS your thread to drift as you'd like. 
Last question first: I haven't messed with them.
First question (THE LOAD):
(5950'> sea level, 58°F)
1 7/8" tube: M 1086 fps/S 28.13/D 11.35
3": M 1185/S 44.68/S 19.02
4": 1230 fps/S 6.39/D 2.23 fps (
!)
(same range, 48°F)
24": 1454/S 13.46/D 6.00
(I haven't shot them over a chronograph out of my 6" 14-2 - sorry!
)
Leaving aside the heat-generating question of whether shooting THE LOAD is advisable in .38 Spl revolvers (while it's worked for me, I can't say if it's safe in anyone else's guns - one must research it on his/her own, think for oneself and do what makes oneself comfortable - always remembering to be careful to follow safe reloading procedures and work up to any load), it does seem like a remarkably consistent loading - if someone wanted a low-stress-but-decently-powerful load for a .357 Magnum revolver, one could do very well with this one. (I'd note that many factory 158-gr
.357 Magnum loadings produce more blast and less velocity than THE LOAD out of a given barrel length - for instance, the 3" tube threw a Magtech 158-gr bullet at 1115/36.33/13.78 on a slightly cooler 50° day and the same gun threw the 145-gr Mag STHP at 1167/42.93/17.97 that same day). But if you want top power out of a carbine, Lil' Gun seems to be the way to go (same bullet, M 2002 fps/S 19.52/D 8.66 - hard to beat them numbers, eh?
).
I only use Tennessee Valley Bullets hardcast 158-gr LSWCs with this . . . I've found that they seem to give me a bit more velocity than other cast bullets I've chrono'd over any given powder charge - and they're fairly cheap and made by a first-class guy and board member (nkjnut).