One thing though - I try not to use chemicals too much and have found an excellent bug remover from glass and headlights is any cheap sort of nylon pot scourer + hot water + a bit of work. I've even been known to use it on the stainless - it's not done my pots any harm after 15 odd years and it's not created any lasting issues on my bumper or mirrors.
J
I would be very careful with nylon pot scourers. The same material is used to make the circular swirl marks on metal plate. I used a new one to remove something like a chemical resin that splashed on my windscreen (truck load spill?)on the Autostrada. I suspect that if I had used a used potscourer it may not have been so bad but I will never do it again. I have spent hours with a buff and jewellers polish to remove the worst of the scratches.