I'm curious, well I've been using the following for a while, and I still love their quality there's just some instruments I'm in a need to look for. The ones I currently use are

EWQL - Symphonic Orchestra Gold
EWQL - Colossus
EWQL - Vapor
EWQL - Ministry of Rock
EWQL - Drum Storm

I'm planning on getting Symphonic Choir sometime in the future as well as Voice of Passion but of course despite these VST packs, that are really space killer. They are missing some instruments..well that's probably because these instruments aren't as commonly used but I'm looking for a VST that contains good quality of the few.

Accordian
Orcarina
Pan Flute
Koto and various other Japanese cultural instruments
Various Acoustic Guitar types.
and a few other instruments that have currently slipped my mind.

There's a decent pan flute and numerous guitar sounds you can make some good use of in Reason 4.0. I really don't recommend you use synths for these things -- when I want to use instruments that sound better when they're actually real, it's usually in the context of an electronic style and so the lack of realism is covered up by arpeggiations and synths.

Synthfont is a good MIDI writing program that uses Soundfonts and plugins.

You can find a myriad of good soundfonts for free at SF2MIDI (http://www.sf2midi.com/). Though you will need to register a free account to download them.

FL STUDIO, anyone?

FL STUDIO, anyone?

I'm using FL 6 right now for my music projects..it's ok.