Is there any known limitation to the management interface if this interface is put to work like any of the other ones? meaning for example, are there any known limitations if this interface is connected as the WAN interface for the ASA?
Yes, I'm sure. It's called a management interface because it comes pre-configured with an IP address and a DHCP server so that you can power up a new ASA, connect a computer to that port with an Ethernet cable, and fire up ASDM to start configuring the ASA without having to do anything with the console port. Even so, the management port is still an Ethernet port, and if you remove the "management-only" command from it you can use it just like any other interface. One thing that's a little special about that interface, however, is that it's only a 10/100 port, even on the higher-end ASA boxes that support 4 (or more) 10/100/1000 ports, so that might limit it's usefulness. I don't know if there are any internal hardware differences with this port compared to the others, such as bus speeds, etc., but it's still a 10/100 interface. I've never seen nor heard of any performance issues with the Management interface, so I'd go ahead and use it if you need it and don't have a problem that it's only a 10/100 port.