While these are great speakers for the money generally, one or two things i would consider to improve the overall use.
1 - a better power switch. I have come across similar power switches on other high powered speakers and over time they do fail. Probably due to high current. Maybe a delayed relay would be better. I think Powecon instead of IEC would also be more pro.
2 - A balance control between the upper units and the sub unit. The DSP is useful, but in certain situations rolling off the bass isn't the same as just simply setting the level. I believe that the RCF units at the same price offer this.
3 - The cases from DB are really overpriced. They need to re-evaluate the margins their making for what are essentially soft cases. There seems to be no options from what I see. Bit of a captive market!
On the good side, they are generally well screwed together, when you get you mix levels right they sound great and kick out plenty. (sometimes too much)