Buying online is a hassle unless you buy online consistently, know your stuff and know what to do. I purchase most of my clothes online and from buying online for the past 3 - 4 years on eBay etc. and I still get worried over sizing and sometimes get disappointed when I receive a certain item that isn't up to my expectations but that's how it is. You'll get by with some items happily and you get burned in other instances.

You really need to know your size and do a lot of research on a certain item. If it is possible to ask the seller questions, do it ! It helps a lot but in your case, I suggest you go to a DM store and see what you want, try it on and buy online. Chances are you'll be satisfied as your expectations and the item bought won't be too far off.

May I know why do you opt for Amazon instead of buying it in our local stores ?