Curtis is definately worth at least a look, and worth a roster spot depending on your team size and/or on your depth at WR (or lack thereof). MacDonald's a reach IMO.
The thing is, with WR's it's awfully hard to find consistent production off the WW (or anywhere outside the top 5 or so for that matter). While there will likely be a WR who will put up solid numbers late in the season (when you very well might need it to get you in the playoffs or win you a championship) ala Bennett or Evans Last Year I think that in week 3/4 it's just too early to tell who those guys might/will be.
Still, Curtis and Ferguson are both guys that (if you have the spot) could post solid numbers in any given week. Consistent numbers are another thing.
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