Could you elaborate a little on what you mean by "blew through multiple connectors"? I might be able to give you some pointers if you give me a little more information to work with. Maybe add a picture of the connectors you blew through.
Yup they are a PITA. You need a lot of heat over a short period of time.
The best way I've found is to tin the wire. If you are using a plastic connector, mate the connector to the other half, it reduces the plastic distortion. Then fill the cup with solder. If you do it in one fell swoop you can put the tinned wired right into the liquid metal, otherwise you will need to reflow the solder.
Post #10 of my build log shows me soldering the 8mm connectors with a torch. Those are pretty easy compared to the QS8s.