I use Beadalon and SoftFlex in various grades and strand numbers. I have rolls of each in my supply chest. I decide based on the type/quality/price of the beads/stones I'm using which wire I use. In most jewelry instruction books there is a section in the "how to's" that tells which type of wire/flexibility/strand #s are best for what type of bead or stone, that helps to decide too.
It's just my opinion but for instance, as costly as SoftFlex is compared to Beadalon, I just can't bring myself to use it (SF) on a quicky multi-strand crimpled necklace made with a really inexpensive strand of glass beads that I throw together because someone says they need a pink and black necklace NOW but only have $15 to spend, you see what I mean? I don't think that one is going to last any longer than the other if the finish work is done properly either.
SoftFlex I really truly believe is more flexible and a lot less likely to kink. When I first started beading a WONDERFUL lady that owns a store in Whiteland, Indiana gave me so many tips and one day she asked me about my wire and I told her what I used, she pulled out a piece of SF and showed me right there that she could wrap the SF around her finger etc and it always sprung back, that sold me for using it for more high end pieces or when flexibility is a must.
I've never used TigerTail, have just heard too many bad opinions on it, and the AccuFlex from FMG looks like it would be fine too, I've just never tried it.
If you keep a close watch on your local hobby stores, they will have their beading wire on sale periodically for 50%. If you don't have a HobbyLobby close to you, I think that you can get their sale prices online too. That is when I stock up on Beadalon and SoftFlex. I've compared and at 50% off, it's cheaper than I can order it online even with being able to buy at wholesale since I don't buy in massive quantities, it's still cheaper so I stock up on it. Every once in a while you can find great deals on it too on Ebay in quantity. Just make sure you are buying from a good seller and all that jazz and add the shipping in to make sure you aren't paying the same in the long run as you would at the store. I did that a couple time... DUH.
I've not tried yet the colored wires from Beadalon but plan to get some and make some fun spring necklaces from it and try it out...
I have friends that swear by every type of wire... I will tell you one tip I learned the hard way, if you are going to use very fine beadalon, make sure you have a way of "controlling" the wire on the spool when you unroll it, it has a tendency to SPRING to life and I have literally had an entire spool of 100 in my lap unrolled. LOL...
Hope I helped a little bit...
LAS