Sforzando is a player of SFZ file extremely powerful. The developers have developed Chipsounds and Aria engine. Sforzando use Aria engine single player mode without effects.
The quality of sound output is extremely accurate, I tested in comparison with Cakewalk SFZ and Sforzando is capable of playing WAV files smaller without penalty (like Single Cycle Waveform). The player can convert Soundfont SF2 to SFZ in the folder of your choice (change the folder in "settings" panel).
Filters are good I know that conventional LP6, LP12, LP24 and LP48, which allows me to create all layers of analogue beauty. Editing is done using a text editor (personally I use PSPad) and the file being played by Sforzando is updated automatically making it very comfortable editing.
Reading sample format is WAV and OGG, but I discovered that the FLAC format is also included which allows you to create large banks without keeping the sound quality (to my opinion OGG is not a professional format).
I regularly asked on the forum to know various details of the SFZ programming and I was pleasantly surprised to get answers quickly and accurately (the forum is mainly dedicated to Aria engine).
I regularly use this sampler / synthesizer to create my sets of banks in my own music. Opportunities for external modulation (with the use of "controls" panel) can compete with a synthesizer (such as Synth 1).
Even with large banks of sounds (multi sampled) my processor does not suffer. This is a sampler that does not have all the advantages of Kontakt but is doing well in various situations and is more flexible.