Kick back reducing chain.... is a more proper term than "safety chain", as no saw chain is really safe.
Just remember that the are some principally different types of such chain out there:
1) The chain with tripple-hump or just one large one,
on the tie straps between cutters. These are the ones that really suck, slowing down cutting in general, and making bore cutting next to impossible.
Stihl RM2, PM1 and Oregon SL, VG belongs to this category.
2) Chain with a small ramp on the
driver, directly in front of a narrow (not "bullet-shaped" like on Stihl RS/RSC and Oregon LG) raker.
The combined size of the raker and ramp is not much larger than the raker alone on the RS/LG, and I think you would be hard pressed to notice any slower cutting -
maybe there will be a small difference in very long cuts.
Some even say that these chain perform
better than LG/RS for bore cutting.
Oregon LP/BP/VP (++), and Stihl RSC3 belongs to this category.
Carton/Woodsmanpro also have variants of both types, but I suspect that the ramp on their "category 2" chain may be a bit larger than on the Oregon variants.
3) The somewhat bullet shaped rakers on chain like Stihl RS/RSC/RM/RMC and Oregon LG etc were also originally conceived as a kick-back reducing feature - at least according to Oregon.
4) The most kick-back aggressive chain are those with only a narrow raker, and no bumps or ramps, like Stihl RSK.
In addition we have oddballs like the Oregon Vanguard (V), and I am sure there is more.
By the way, this is my post number 2000 here, and hopefully it makes some sence....