[mmoret]

I use Checkpoint on Solaris and Nokia.
The benefits of Nokia are in my opinion:
-Ease of install/management/deployment
-No unix knowledge necsessary
-Clustering out of box with checkpoint

The downside is that you cannot just run other software on your firewall (like DNS, proxy, mail)

I believe Solaris is an enterprise platform with great performance and stability.
The downside: You need administrate a server as well as a firewall.

I have played around with splat and think is great as well, but do not have as much experience with it as with Solaris and Nokia.
We use splat as an standby enterprise management station. I export and backup the checkpoint config and have splat standing by with the same ip as the current management station.

Good luck!
Martijn