Most CD burners today do both CDR and CDRW. A drive marked "CDRW" will also burn CDR. A drive labeled "CDR" will not *necessarily* burn CDRW.
You cannot make audio CD's on CDRW, only CDR. Therefore CDRW is only good for data. CDR media is also a bit sturdier and more reliable, but they're both fairly delicate.
If you're writing data files (sound files, picture files, etc) then the burning speed does not matter. The files will be fine or corrupt...you'll know if there's a problem. Once you start burning CD's, you'll appreciate the speed of an 8X burner! It can take 30-40 minutes to burn a full CD at 2X. 8X is 4 times faster (supposedly), so you do the math
CD audio is a bit different however. If an error goes to the disc it might be hard to spot. The CD player (which isn't as reliable as your CDROM drive at reading media BTW) will still play it (or try to). The most *reliable* burning speed is of course the slowest speed you can burn at (1X or 2X).
All CDRW drives will burn at speeds slower than their max rating. An 8X drive will do 2X if you tell it to.
In summary, everything you were afraid of is false

Your friend was incorrect if he was talking about "hardware" as in "the drive"...CDRW drives are not worse than CDR drives...and in most cases they're one in the same.
What you have to worry about and really research are the various brands and models of burners out there. That's the most important thing to look into if you're looking for reliability. I cannot help you there, but others here can. I can say that HP has a slew of bad drives on the market that are generating a massive negative response.
Slackmaster 2000