I just did a little googling. The World Sport seems to have been a low- to mid-level bike in it's day (hopefully yours is more "mid" and not so much "low"). Maybe post pictures of the frame, components, decals etc. in classic and vintage, and see if people think it is worth maintaining. Any new bike you get for $300-400 will be ok, but nothing special, and the Schwinn may well be better.