At tihs point, air transit time from the Far East (China/Hong Kong) is about 2 weeks for air mail. Just about all reputable dealers ship using some sort of tracking, so you can see when the item was shipped as well as when it hits the USA. So if you are in the USA, I'd say it is pretty rare for transit times to get up to a month from China/Hong Kong.
The sellers in the Far East are typically less expensive, however if you have a problem (frankly not very likely), the cost of return shipping, and the delay in replacement is a major nuisance. If there were serious problems with anyone who advertised on these forums, it would show up here. I can only think of 1 advertiser in the time I have been here (which has been quite a while) that had serious customer relations problems , and they weren't advertisers here for very long. This is a fairly vocal community when it comes to problems with suppliers.