Personally, I prefer to use the Bug-O stitch welder for that, when it will fit the application - but I know what you mean. I have tried the automatic lenses out. As I said, I don't weld much these days.
My standing comment to our welding supply salesman is that I'll buy an auto-darkening shield when his price comes down to $20 or less. I figure if calculators can be had for $1, then the shields will come down in price too (although I may be retired or long gone by that time.)
Chet