Performance can be maximized very readily;
If V2Parser is set true in RapidSpellWebLauncher/RapidSpellWInline then there is an automatic 10- 20% performance hit, this is because although the V2Parser is more accurate, it is also slightly slower. We recommend the use of the V2Parser, but if performance is an issue this can be set to false. Note that V2Parser=true is needed for URL/Email ignoring.
Dict Files do load quicker than DLL dictionaries, therefore they are worth using if Dictionary Caching is disabled.