Any of the guys 19 or older are suspect as prospects. Sure, they could develop but why did it take 3+ years for them to be found?
Same reason a kid in the States can go undrafted out of high school, to #1 overall 3 years later.
Not saying any of the kids are now premium prospects, but I wouldn't completely write them off either. A lot of development can take place physically over a couple years. I get the sentiment ... the younger the better in terms of 'foreigners' but you never know.