Hell, even a Sylvania or RCA gray plate is a pretty awesome tube to try. I don't mind Groove Tubes so much. People on her bag on them for rebranding tubes you can get for cheaper, but by and large I've had very few failures with them, and honestly, I can't tell the differences in tone with any of them. Some can, but it's so subtle that I can account for most of those tonal changes just by turning a tone knob ever so slightly, so I don't sweat it. I mainly get NOS because they last longer, but I don't mind the sound of new tubes.