Hi. Does anyone know if replacing the prop motors on P4 uses same, simple procedure as its predecessors or is it more complicated? I've had good luck, never had to open mine or done any mods to it. This morning I had an 'incident'. Overall bird is fine but one motor seems to lag a bit. I'll spend the 20 bucks to replace the possibly damaged motor rather than chance a crash due to motor failing at high altitude. On my way into work now - wanted some feedback whether I ought to order the replacement motor (s) or send bird out for professional repair? Thanks.