I hate to cast aspersions on anyone, but pre-made coils like that, especially lesser known brands, can really vary in quality, and rarely for the better. For that reason I avoid them outside of proven suppliers like AVS, where everything is well made and a they work with is SS. Nothing wrong with other metals, and it's just my personal preference, but there is too much crappy work on the market with that stuff, especially the bargain priced fancy coils.
Of course the best way to assure you know exactly what you're using is to make your own, but not everyone wants to or can. If you are going the prespun stuff look for quality and not the cheapest prices stuff. Making a quality complex coil requires skill, and fks with good skills don't work on the cheap.
You can also check out the suppliers forums here. There are some folks who specialize in building complex coils to your requested specs and turn out nice coils, but not necessarily the cheapest. However if a bargain coil doesn't work well the more expensive coil looks like the better value. Besides, if you take care of your coil and clean it regularly, it can last months, so it's not like a)3 drop in coil you have to toss in 2 weeks. That makes the better quality builds an even better value as for a few dollars you have something to keep you running much longer.
