The plug is particularly useful on hollow stages and/or in rooms with lots of echo.
Been using the single port, basic 1203 and similarly the basic mesa d800 for 5 years now. In theory, lots of adjustment options were nice, but in practice I never used them. This is the best sounding, most portable, gigable, plug and play setup I could find.
Exactly.
I was constantly swapping and tinkering with amps, cabs and drivers for nearly 40 years, and never completely satisfied.
I got pretty close in the mid-late 70's, when I discovered EVM-15B's and L's and Thiele cabs. But that still always seemed to be missing just a little somethin'-somethin' with my '64 P-bass. I wanted hi-fi, but smooth. The harsh tweeters in most "modern" bass cabs never sounded great to me.
I got worse when I picked up my first 5-string in the mid '80's. Now I wanted to hear and feel a solid fundamental on the low B, and nothing did that justice.
I got a pair of Flite 103W's in the late 90's, and they helped a lot for low-volume applications. I continued experimenting with boutique cabs for years, and while they always sounded great, I never found the magic bullet. Ditto with heads.
I tried PA gear for a while, and if I had a enough $$$ and roadies, I think I could have been pretty happy with the big Meyer Sound rig that Anthony Jackson uses.
It wasn't until the Greenboy cabs came out, that I started to see the light at the end of the tunnel. The final piece to fall into place for me, was Duke's Thunderchild.
After that, I was done. I continued on with a few reflexive amp swaps for a while, and finally settled on the MB Fusion. I could have swapped the G-K for the D800, or maybe a Bergantino, but truth be told, I couldn't be bothered.
There are dozens of great heads that I could use with my TC112 or a pair of 1203's. Once these cabs came out, I was done like dinner.