I've used the old standard #9 and #10 for 30 years. Finally went to an auto darkening helmet. There are differences you have to consider when using them. If welding outside, I leave my auto helmet in the barn and reach for the old standby #10. If I'm welding by the door, same thing but with a #9. Why, the sun lite darkens the lens before you get an eye ball on what is you want to weld, thus going off track. Maybe some of the high dollar helmets have an adjustment to eliminate this but my adjustment just doesn't do it. I don't have a problem with bobbing my head if I have to when the situation requires it to drop the helmet.
If I'm indoors I use my auto helmet. But I have changed the bulbs in the light fixtures in my shop so the auto feature doesn't go crazy on me like it does outside.
So in a nut shell, it's lighting. Control the light around you and you will be able to track that weld perfectly.
Hope I helped you and good luck.