There are a number of considerations that are worth bearing in mind if you want to choose a raincoat that is suitable for the purpose you have in mind. There is no point in choosing a coat for off-road cycling that, when wet, weighs more than your bike. Or a coat for the school run which leaves you standing in the playground in mid-December soaked to the skin with teeth chattering louder than a school bell.
Therefore, right at the top of the list, your first consideration must be performed, or in other words, what conditions are you expecting your raincoat to cope with? Once you have decided what you intend to use the coat for, you will be more likely to spend your hard-earned cash on your perfect go-to jacket, one that is worn time and time again, rather than being consigned to a forgotten peg to gather dust.