Well for AS (Asia) it would have been awesome. For SA (South America) things are different. In 2013, there were 18 selectees from Grenada. That means there are more or less 10 visa numbers available for Grenada
Here is your dilemma: if you do AOS, you are almost guaranteed NOT to get a visa number. Because by the time USCIS sorts out your stuff and gives you an interview, bunch of your countrymen will already have their interviews scheduled/done. Your number is very low, but so is your country's quota (unless they chose more people this year from your country which we don't know yet).
You will be current in October, chances are you'll get an interview in December, January, or even February, which could be too late.
If you do CP, you have more chances; you'll get your interview probably in October, before other 15 or 20 people had a chance
to claim all visa numbers. But remember this; if you don't get a GC, you are not coming back to US on J1
Your number is low so chances are you'll get an interview before most of them, but all it takes is three people before you with spouses and kids, and all 10 or so visa numbers are gone.
There was a guy from Belize this year and he had no idea that there were only about 10 visas available; by the time USCIS gave him an interview there were no numbers left.
You really have some thinking and deciding to do. If you think it's worth risking J1, I'd say go ahead and do CP.