Soprano is more difficult to play in tune than the bigger horns.  In your position, getting a horn that guides most strongly to good intonation would be my most important criterion.  Some horns are twitchier than others.  Good quality Taiwanese sopranos at moderate prices are available under the Antigua and Kessler brands.  Kessler in Las Vegas sells models from both brands, so there's a good chance they can match you with a horn that fits your criteria.  Jupiter, Chateau, and Cannonball are brands of good quality horns distributed to music stores, so you can try them out.  If you're considering a used horn, the Vito (Japan) soprano is a good horn made by Yanagisawa.  I would be cautious about Jupiter or Antigua in the used market because earlier examples from those companies were not of the same quality as their more recent products.