PAM249 houses the basic Unitas movement while the PAM448 houses the in-house P.3000 movement. So I'd consider the PAM448 an upgrade over the PAM249, but that is just my own personal opinion.
Cheers,
Anthony
This message has been edited by AnthonyTsai on 2012-01-17 21:23:41

1) water resistance : 30m for 249 vs 100m for 448
2) plexi crystal : 2mm for 249 vs 2.8mm for 448
3) word "California" printed on the inner bezel ring for the 448 and none for the 249
4) burgundy coloured strap for the 448 vs honey brown coloured strap for the 249
5) wordings on dial at 6 oclock just below the "rail track" - L Swiss L for the 448 and L Swiss Made L for the 249
cheers,
Horo