As far as I know, almost all balls have the same shape core from 16 thru 14 lbs. Some keep that shape in lighter weights, but most stop at 14 lbs. Having said that, while the core shape's the same, the numbers (RG, RG differential) are normally a little different, but not usually in a large amount.
As to pin carry, I find that 14 lbs CAN carry as well or better than the heavier weights. You will get increased deflection, which, depending on your game can help out a lot with pin carry. Personally, I find that I carry the slightly heavier hit better (fewer 4 and 9 pins), but I do give up a bit on the light, mixer-type hits(a few more 5 and 7 pins). As to the 10 pin, I rarely leave ringing ones anymore, mostly flat ones(6 pin just lays in the gutter), and no more of them than I can remember leaving when I rolled heavier equipment.
The most important thing I found when dropping to 14, was to make sure I got out of the ball CLEAN. If I hung up, or dropped it, I got some ugly results(5-7s, 5-10s, 8-10s) on what looked like reasonably good shots. I almost never leave the 9 or 4-9 anymore, unless I'm almost dead on the head pin.
drillbit