Yes the nice ladies company is , myuniquesolitions. What I like about her powdered solders is the lack of flux in the powder. Yes I can work with the solders that have flux incorporated into it whether paste or powder. What I hate about that mix is with the powdered version I encountered a mushrooming effect as the mix warmed up before it flowed. That happened with minute amounts and larger amounts. I tried moistening more, and alternatively drying it out first. The same problem occurs. Its more that the bubbling of flux you get when you apply the two separately. Having the two separate FOR ME was a way to control the variable of expansion caused be the flux boiling away. As to my using powdered solder it depends on the job I’m working on. I rarely use it other than filigree. I use sheet I cut to the size needed. I use wire both for touch feed soldering and melted for pick soldering. The solder used is also as variable as to how I set up to solder. I may use a charcoal block, or solderite board. It could be a tripod with fine or large wire screen. I use titanium clips and old stainless steel dinner knives found at garage sales to hold work. I could go further with heat barrier methods, but you get the idea. It depends on the piece you are working with that the individual working will use. For me personally paste solders have no space in my work room.
I also don’t have a problem with solder showing after I’ve made the piece. I learned a slick trick on how to keep the amount of powder clinging to the piece. Excess is collected to be used again since it is not contaminated with any other substance. If by chance I see solder has made it to where it shows, that is where my flex shaft goes to work.
Sadly now I do few pieces of anything. After shattering my right wrist and forearm, I find it still difficult to work more that an hour a day. I can do the work, but the hand cramps up and quits working. So I no longer do stage demonstrations of jewelry and metal working with the Utah Shakespeare Festival. It was a decade of fun working with them.