I'll add a post of enthusiasm for the kind of unbelievable array of free pianos available at Pianobook. For anyone not familiar with the free Decent Sampler it's a no brainer to install it. Most of the instruments on Pianobook have DS banks, and many have sfz, which can be loaded into many free software samplers/players. (Also Kontakt format for those in that world.) It depends on what the instrument creator uses or has easy access to. It's one of the true gifts for those with no budget wanting to have a library of instruments.