The quick clot powder (the one that had the rumors flying) isn't made any more. Other forms of quick clot products are gauze based, like impregnated sponges or roller bandages. The powder was improved with gauze carriers because in a windy environment it would blow around as you were trying to get it into a wound, and because pouring it relied on gravity you could only use it on patients in the right orientation - which made it hard to impossible to treat patients still entrapped.
I've used, and seen used, QC powder, in combat. I've talked to surgeons who treated wounded soldiers following use of QC, and I've read the professional medical literature on QC products, including the powder. My hospital now has the version for use on patients with bleeding disorders who bleed from angiocaths and the like - used like tegaderm over the caths, too.
AFAIK, there are no confirmed reports of any untoward results (burning, etc) from using the powder. The military did look for them, especially since the Army had a lot invested (pride, and lots of $$$$ for development) in the Hemcon bandages (which have since been pulled) and the other services decided on QC instead. Stories about surgeons having to remove it? So? Thats what they're doing in there - GSW or blast injuries have to be cleaned out (debrided) from all sorts of stuff. An ounce of a sterile powder isn't going to make much difference in the washout.
Because of the stories, the Uniformed Services University of Health Sciences did a controlled study of QC powder, to see if it 'burned' live tissue. The finding was no.
The way the QC material (zeolite, a mineral form of aluminosilicates) works is by adsorbing the water molecules in blood (from plasma), locally concentrating the clotting factors in blood - letting them work better. It doesn't 'cauterize' anything. The pores in the mineral are kind of like goretex: small enough to let water in, too small for any larger molecules. The adsorption reaction is slightly exothermic (heat generating) but not to any significant degree; and when the alternative is exsanguination would not be a major issue anyway.
The use of QC products is simple: For heavy, usually arterial bleeding (bright red, spurting, etc) where other forms of hemostasis (direct pressure, etc) are failing, or (say) a tourniquet is impractical (groin, abdomen, thorax, head/neck injuries) plug the hole with a QC product to get the stuff in there. Put a regular bandage (4x4, kerlix, whatever) over the QC product. Put a pressure dressing on top of all that, tight. Use an ACE or similar elastic bandage if possible to tighten it some more (not on neck, obviously). Call for transport to higher levels of care ASAP.
www.zmedica.com has training available for their products, if anyone wants to avail themselves.
There is another, similar product in use in the military: Celox. They (celox) also make an impregnated gauze product, and a powder-like material with an applicator to get it into the wound. Use of the gauze products are similar to that of QC, the powder-like product is 'squirted' into the wounds. It works somewhat differently, it's based on chitosan, a polysachharide that is naturally metabolized by the body, and forms a gel that assists clotting. I've not used it but have talked to physicians in theater who have seen it work: It's about as effective in real life use as QC. I believe the current Army protocol is to use both.
Besides the hemcon bandages, there are a few other products that were approved for use and then removed when they were found to be dangerous. One product was found in several cases to transport itself through the bloodstream and cause thrombosis (clots) in vessels where you're rather not have them - the brain, lungs, heart.
FWIW, I carry QC products (which I buy). I think they're worthwhile for the types of injuries that they are intended for. They're not for every little boo-boo, of course. Fortunately, I haven't needed to use them outside of the military, and I have more leeway in using whatever I want than an EMT or first aider does. But, I think I'd use them if available, no matter what.