Go with any you choose.
Assume any you choose has zero security. Don't trust them with your personal stuff. Anything personal or sensitive you upload should be encrypted before uploading. All will be roughly the same speed.
If you want to pay, then there are many options. Mozy is used by many.
You could use JungleDisk (with Amazon's S3 service), or use what I use: Strongspace (I know and trust the guys that run it).
http://www.jungledisk.com
http://www.strongspace.com
http://www.mozy.com