It is true, the plastic will be acceptable and ok for a while but with age and exposure to weather and elements, it starts to get that weathered look. There is now plastic cleaner for them that works but it's just not anything that will keep it from looking weathered and hazy after a period of time.
i love my half doors with soft uppers - windows don't bother me at all.
they both have their pro's and cons..
i don't feel like knocking the pins out of my hinges to take the doors off when its a nice day out.. kind of extreme so thats why i love that i can slide out the uppers in 10 seconds
no issues with water leaking in etc - only thing with the half doors is you either need to make your own.... or get a random company to make them for you $$$$ CCOT-then get someone to make the uppers... $$$$$$$$$$ or get them from Pakistan(SouthBoston) if he has available which i have.. just paint them (your best option but might take some time to get them)