Those are basically Kanthal. So they're basically 24g / 28g fused claptons (two cores in parallel).
Ni80 or SS cores will heat up much quicker, and a SS wrap wire for many produces a crisper taste.
However, the resistance is often lower.
That's a pretty thick wrap being 28g, imo, but should be more durable. It may have a slower ramp-up time. Some people feel thinner wraps produce better flavor, but for me it comes down to how many cores & how wide the wire is.
The thinner the core wires, the faster they heat up. As you approach 28-30g cores, your coils heat even faster.
Stainless fused claptons
& if you don't really know what kind of wire you like, look for a
sampler pack
another
here
Whatever you're building for,
use a tester to build on. Get
one of these to hold the coil in place & keep it from bending when you tighten the leads. I'd recommend good, strong flush cutters of some sort to snip the ends off, but please make sure to use eye protection when snipping coil leads (half because of the piece of wire coming off, and half because the blades of even high-quality flush cutters sometimes break off)
Some ceramic-tipped tweezers may also be useful for working out any hot-spots that might be in the coils, or some of the coil master ceramic sticks for springy wires.
If you decide you want to go the stainless steel route,
AVS has some really clean SS wire to choose from and has some pretty good instructions for getting them firing evenly. With Fasttech coils, (and reportedly also a lot of their wire) you probably want to clean them because they're often a bit dirty.
EDIT: If you haven't got an ultrasonic cleaner, sticking them in a cup of some hot, soapy water for a little while, then rinsing well should get a fair amount of oil & dirt off.
I use
TEMCO wire bought directly from their website with free shipping, it's pretty clean stuff but does need a light dry burn & rinse before use.
They also carry SS wire. Seems like the page for their SS isn't working, so I'd try Amazon.