Need2Slin is my favorite nutrient partitioner, and I've tried all the ones out there. However, everyone responds differently.
Is Need2Slin or any other partitioner better than LG Slin, that depends on you and the use.
IIRC, Slin is basically ALA and cinnamon (maybe one other thing like chromium?). At that point, you could basically use regular ALA and try that out. Puritan Pride has buy 1 get 2 free, and you can get it very cheap. ALA is good for a lot of people, and has some good health benefits.
However, ALA is not the best form of ALA. Na-R-ALA is ~100x better IIRC. There are even studies showing (in rats/mice) that life expectancy increased in those using R-ALA (not sodium bonded, just the R isomer), but decereased for ALA (S and R isomer racemic mix). The S isomer is not natural or produced in the body, so it's a waste product that could have negative effects. That was enough to turn me off of ALA and go for Na-R-ALA.
I currently use Na-R-ALA in Glycobol/Need2Slin (use both interchangeably) for my ALA and glucose control. I feel this is probably the surest way to get the health (and insulin) benefits. Need2Slin also has several ingredients that activate cAMP for further weight loss/control and insulin control. Need2Slin also does not build up toxicity like products containing Vanadyl can do (particularly the form of VS in Glycobol, BMOV).
So, if you want to try it out for $10, you can (probabbly should) and it may suit your needs. However, after you've done that you can try another nutrient partitioner if you're not satisfied and see which works best for you.