This subject does the rounds on the forums a couple of times a year. If you make 1:72 kits, stand 72 feet away from the real thing and I guarantee you WILL be able to see panel lines, the statement that you can't is factually incorrect, they are NOT an artificial artefact. And anyway, how many times do you look at a model from 1 foot away, we all dive in for a closer look. Second. Even if you can't see them (and I will concede that at times, in certain light with certain airframes you won't see them), in my opinion a model with no panel lines will look bland and toy like. This is where the artistry of modelling starts coming into play. Third. Washes. If you want dark panel lines and you are pleased with the result then great, we only make models for our own enjoyment and satisfaction. Personally I "aim" for realism therefore I avoid stark contrasts with panel lines, I try and pick a complimentary tone to the finish. In places such as cockpits and wheel wells then I up the contrast as light levels are usually low, this is using the was to fool the eye with the intension of creating realism with false shadow. This point is coupled to panel lines in the second point I made. Bottom line, it's your model so it's up to you. But if you want to go for ultimate realism then you have to address canopy thickness, undercarriage door thickness, seam lines even paint thickness and visible brush strokes! For those who paint with a brush light coats building up the colour with polishing in between will result in a smooth finish without filling in the panel lines. Ultimately, know what you want your model to look like and aim for that finishing how you like.