Ill be doing a full correction on my altima (second one in its life) from what I read/experienced, nissan's have thin and soft paint around a 1/4 of what you get with a german car. Is 400 going to be to abrasive to correct it? I have from menzerna GF400 SF4500 SI1500
I used FG400 on subaru paint, doesnt get any softer then that. Again, alot has to do with pressure, pad and working time.
No worries with that combo. If you are unsure, don't go any more aggressive than a green pad near the edges. And German cars don't have any more paint than the average Nissan. Almost every German car I've done including the Merc SLS AMG has been around 100 microns.
I definitely agree, robots are scary good at laying the coats. My 2012 Nissan NV has 66 microns in some areas. Eh! Not one section over 100. On most new cars the paint is thin. However we have done a few Fiats with most readings over 140...and of course Rolls Royce. BMW has only gone down in readings and overall coverage. Audi has stepped it up. *Rule of thumb: cut wisely...always measure and always test before going full boogie