I have that same Lisle valve spring tool
Works fine. I've replaced quite a few sets of valve seals without even pulling the heads off.
I also have one of those big c clamp style spring compressors. I use both at different times. Both have their place.
I'd like to find a c clamp style that is air operated one of these days. But not in a hurry as I've gotten by fine without all of these years.
One day I'll find one at a garage sale or swap meet...