sherbearjt, the Sony 350 has the new eInk pearl screen which is universally considered to be better than the vizplex screen your 300 has.
You haven't indicated any real dissatisfaction with what you've got. In my view, one should always wait to upgrade until one is dissatisfied, because the prices are coming down and new models will be introduced.
The Sony 350 goes for $150, not including the cover and any extras. With the $75 credit you already have, the 350 would be a good deal. You might also look into the Sony 650 which costs I think $70 more.
|