In looking at the features it offers it looks to be fairly basic. It can perform lookups against a single domain. With
bind you can have as single instance servicing multiple domains as well as having much more complex setups.
Samba 4's implementation does give you the ability to chain an additional server into the mix so you can have some of the resolving done by Samba 4 and for anything it can't resolve it can forward these requests to another server, however it's still limited to the one domain name.
You can do this by adding these lines to your
dns recursive queries = yes
dns forwarders = 192.168.1.5
Based on your description it's not enough to say conclusively whether you can/can't use just the Samba 4 DNS server, I think the main breaking point will have to do with how you are using domain names across your servers as well as any virtualhost's you may setup within the HTTP service.
For example I have a fairly complex setup where I host multiple domain names on a single instance of Apache. I then use forms of these names to access backend servers such as databases using forms of the domains used to access the HTTP server.
So if someone were to come in and access www.somedom.com, they would get their content served and the HTTP server would've been accessing the database server using the name db.somedom.com.
To achieve this I setup multiple domains within my DNS Bind instance to facilitate this.