Sale, of course the 200 can't equal a 300 or 400 on payload or performance - that's why Mr Boeing keeps bringing out bigger and better ones.
But what about acquisition cost? You could use the same argument to say a 700 or 800 would be so much better than a 300, or an A320 better than any B737. But who can afford it? Not little islands in the Pacific. Is that not why Air Nauru is in the poo? Aviation aspirations above the region's real needs, pig-headed national pride helping to bankrupt an entire nation, an airline grounded for over half a year and on many previous occasions because it either does not have an airplane or it is chained to the ground somewhere by the bailiff. And will one debt-laden 300 really end up being more viable than three 200's owned outright by Mr S? The 300 is rapidly becoming just as much an orphan as the F28 or Fokker 100 and may not be easy to support to full ETOPS anyway. The 200 may also be seen by some as a bit of an orphan, though there are still over 600 in airline service. That's a lot of potentially spare engines and airframes as airlines who really can afford bigger and better models park their 200s in the desert. The Ozjet idea has potential legs as a way to provide cheap transport to the islands for at least another couple of years. Maybe it is what they should have done in the 1st place.