We did a job a few years back building storage silo's that were 410 we used a 410 wire (don't remember the manufacturer)with 98/2 Argon/0x and pushed it up into a spray mode. We also used ceramic backing tape and welded from one side only. The silos were rotated and welding was done on top in a flat position. You could not run this out of position. Some of the other suppliers qualified a procedure using 309LT. I chose the 410 w/ a spray mode for mat. cost and deposition rates.
I use a Lincoln flux cored wire here at our shop for carbon steel, 71M it runs excellent in all positions. We also use a Kobe wire that is less expensive -DW50. It doesn't run as nice as the Lincoln but for the price its a good choice. All of our shop work is done with 75/25 Argon/co2 shielding. Our field crew uses straight CO2.
Tracy