Hi Guys, need your advises on the following.

I already have a 20G 2.5' external HD bought some years back and realised that 20G is too small for backup purposes. As such, should I just

1) Buy a 200G HD to replace my existing 20G while retaining the cover or
2) Buy another external HD like the SEAGATE 200GB (7200rpm/Firewire+USB2.0) External Hard Drive that has a pushbutton backup.

Any user reviews on the Seagate HD with the pushbutton backup model??

Thanks in advance!