Like the VBR, the Plus includes multi-NAT capability with the ability to take up to 10 WAN IP addresses and assign them to ranges of private LAN IP addresses. This lets you, for example, put more than one LAN client in DMZ (one for each WAN IP address you have), and also lets you have multiple virtual (mapped) servers of the same type (FTP servers for example) operating on the same port. Also like the VBR, you can define 8 different DMZ machines (if you have the WAN IP addresses to assign them to!).
What you won't find is any sort of port range mapping. The VBR only allowed port range mapping through its "Special Applications" feature, which didn't handle static inbound port ranges. Update 10/24/02 SMC confirmed that they deleted port range mapping on purpose because of the Plus' small/medium business target market. They suggest using DMZ as a work-around.
The FW has only single-port "Virtual Servers" that don't support server "loopback". Update 10/24/02 Loopback support has been added by 2.03e firmware.
The FW's Access Controls (Port Filters), and Scheduling Features are carbon copies of those on the VBR, with the scheduling among the most flexible that I've seen.
Again, if you need more details on the Plus' firewall features, see the 7004VBR's review.