Well, I am not a wearer YET. However, I have done lots of research/reading and my first order is being made now by the company i chose. With all the studying i've done i think i can answer your question. There are several different companies and most of them use the same few Chinese factories. So, the hair system you purchase, regardless of the company you use, will basically be the same. There will be some varying of quality with each order, no matter which company you choose. It is not like one company is using a special lace or one company uses special hair. They are all using the same basic materials an techniques.
Don't stress so much about which company to use. Jump in with a reputable company and get your feet wet. Because unless you are already an experienced wearer it will probably require some trial and error before you get the right specs for your unit (no matter which company you choose.)
Because i have ZERo experience wearing hair, i chose an online company that gave me the most help/personal contact and support and has a money back guarantee, and will fix my system for free if i am not happy with it for any reason. I probably pay a little more, but not much more, and until i know exactly what works for me, i think that is the safest route. That would be my recommendation for you.