All of them are used. Some examples from Google :
- A rectangular football practice field is 2 times as long as it is wide...
- Servants at stately homes lived almost twice as long as other Victorian workers
- This exam is two times longer than the real one could ever be
- VS 2005 SP1 redistributable takes twice longer to install
- Backups taking 2 to 3 times longer than usual.
- Group 233 was switched from twice to three times daily milking at 100 d ...