Hello Robin,
My experience on the various questions posed by you. (I am sure that many members wwill not agree, so all I can say is YMMV !

)
1. I have used a Plextor CD Writer carried back from Spore many years ago. Supposed to yield lower CR-2 errors. I did check CR-2 errors on the burnt CDR. My observation..... An external USB Cheap & Cheerful CD / DVD Writer is as good on CR-2 errors. The Cheap External CD / DVD Writer outlived the pricey Plextor
My advice, use a cheap and cheerful External CD/DVD burner from Amazon. Use the money saved in buying original CDs.
2. Yes, a CD Rip Does sound different to my ears and on my setup. The rip software ( eg EAC & dB PowerAmp for windows) both yield rips that sound slightly different.
Even the various playback software, all sound different.
3. While on the topic, to copy a CD, its best (essential) that you rip to an image file. Can elaborate on that if queried....
4. A copied CDR lacks the air and Soul .... The Notes are all there, even the softest ones, but the soul is gone. Sounds silly, but I cant express myself any better.....
In my enthusiasm I had burnt several hundred CDRs...., all trashed... I keep finding (and junking) some every time I spring clean.
5. An Original CD played on a Good CD transport has always sounded best compared to a Hard Disk Rip or a CDR. I do have friends who experience better results via their Computer Playback, but they Have VERY Elaborate Computer Playback setups. I am not there yet.....
Enjoy The Hobby. There is no substitute for actual experience.....
Cheers