looking for some advice from the TB experts. I just got my hands on a MB-210 for my cover band. pretty much gonna be my practice amp with this band and local bar amp for gigs with this band. So I'm looking to pair it up with another cab for the shows to get it to 500watts the 300 should be enough for practice

. I'm just gonna build one so I can match width and depth of the MB-210 so they can both fit in my trunk. I'm thinking a 15 will give it some nice surface area for that extra sound at a show, though im open to a pair of 10s or 12s if they would match up better. I am only using a 4 string and the lowest will be drop d tuning. What would be a good add-on speaker to build a cab with for this situation? I was thinking the 3015LF would just be overkill for a drop d 250 watt cab. plus to be honest i cant find any info on the specs of the neos in the GK combo to match it up, was hoping someone had a little more info to help in my selection.