Yep the first time I used megs tar and bug remover was the last! It stained the honeycombe grill on the front of the car which took hours to remove, indeed only recently have the last traces vanished!
I can however whole heartedly recomend 1z anti insekt - spray on everywhere including trim, leave for 3 mins and then simply hose off. Alternativly tescos are selling some bug cleaner at the mo for 61p! Reduced from £2.67. Its good, not as good as 1z but for 61p............................