Which media is prefered (DVD-R or DVD+RW)

On amazon I see
ridata at amazon for $13.99
ridata 8x $16.99
ridata 8x 50 spindle for $33.99
But most of the people I see buying the -R, why they are not interested in +RW ,as +RW can allow bitsetting and I can always erase and rewrite on it.
Which one I should Buy,

I personally prefer - for R and + for RW.
I use DVD-R for backups, movies and games.
I use DVD+RW for temporary storage of files (in case my hard disk is nearly full.)

In choosing which one to buy, it’s much dependent on your use.
If you want to keep a copy for quite a long time, I suggest you buy DVD+/-R.
If you want to store some files temporarily, or to use it like one more small harddisk, you may want to buy a DVD+/-RW.