But do they have a higher rate of success with low budget prospects? Data?
Currently, there are 72 players on the two DSL rosters. The vast majority of these kids will never play in the FCL. Yes, a few of them will develop into useful prospects. But most of them... if you don't regularly look at DSL rosters or box scores, you've never heard of them, and never will.
The top of the market is different - and it's not clear that the Phillies' relative difficulty there has anything to do with scouting, as opposed to their relationships with specific buscones, and their relative effectiveness at bribing those buscones. (There's no point in playing semantic games about what goes on in the Dominican, in particular.)
You know... I don't like the idea of drafts, because a draft denies young amateur players the freedom to offer their services in an open market — at least in the United States and Canada, where, in the absence of a draft, there would be rules (about agents) and laws that would tend to keep such markets relatively open. But in the Dominican? A few buscones basically own most of the top prospects, so there really isn't an open market; it's more a case of a few buyers competing to grease the palms of a few sellers... and the sellers aren't the kids with talent, but the buscones, who get paid under the table. An international draft, as restrictive as it is compared to an actual (properly regulated) free market, would be an improvement — signing bonuses might actually largely go to the players, not to the buscones who "own" them.