As important as the sounds you get are, the biggest problem with most keyboard strings is that the arrangements suck. If you have a decent patch, but you have it playing a real string part, it sounds pretty good. Most people just play block chords and pads, and they sound really boring. Spend the time to write a real string part (or get someone who understands composition and counterpoint to do so) and you will be happier with your string parts, even if the tones are only mediocre. You get a lot further with a well written string part than with a really expensive sound module.
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