The 300 & 350 are very similiar, this would be a much better comparison in my opinion versus choosing between a 200 or the 300 for purchase. Sounds like your "friend" is looking into a purchase. Depending on his needs, wants, goals, desires, etc, etc, I would go with a 300 hands down and no questions asked if money is not a major object or deciding factor. You have so much flexibility with the 300 (3611lbs/fuel, bags, full pax) that you probably will be much more limited with the 200 although the 200 may work depending on his or her needs and wants.
Both are pretty good birds but the 300 will possibly offer more in the long run depending on what the potential owner intends on doing with it.
good luck
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