Im unfamiliar with the equipment that you mentioned so i cant tell you which one to plug into. however i can address the buying your own DI box issue.
If the sound guys in your area are anything like the ones in mine, buying a box would be a waste of money. The sound guys i have the pleasure of working with always insist on using their box. They always ignore the direct out on my amp. Which is no small feat considering its right next to the quarter inch input jack which im already plugged into and is conveniently located right next to it.
Now with that being said, you might have some really cool sound guys in your area that are willing to work with you on that. Some will mic you AND di you if you ask. it all depends on the sound guy, how big your band is, whether or not you paid him, whether you showed up on time and the other bands didnt eat into your time slot, as well as million other factors.
If you think having your own box would help then by all means, get the box. i would just be sure to get a good one, more importantly a brand that the sound guy would recognize and trust. if he thinks your box is sketchy then he will just want to use his. he KNOWS what his own box can do. he doesnt know what yours might do.