EXS 24 Logic Sampler Users Group

hi everyone,
I was wondering if anyone can tell me what seems to be the best piano
emulator i can run with logic on PC? either through EXS or as a vst plugin?
I dont want to buy just anything only to realise its rubbish! I would like
it to sound as close to the real thing as possible, a concert grand maybe?
all the presets and GM pianos just seem to have a fake sound to them, i know
im not going to be able to reproduce a piano exactly but would hope there's
a package out there that is better than these GM pianos. How about any FX
pesets to give a better sound with what is on offer too? this woulod be a
great help.
Many thanks

Fred