Deep Outdoors does make some high quality (albeit expensive) stuff.
Their backplates are finished as nicely as any I have seen. However they only allow the use of 1" crotch straps, whereas (for example) the newer OMS plates have slots for both a 1" and a 2" crotch strap.
The DO Matrix Freedom and Matrix Custom are as nice as any BPs in their category (Transplate, IQ Pack, etc.). I initially bought a Matrix Custom LTD and I liked it, but I soon switched it out for a simple backplate and continuous webbing harness.
I don't care for Deep Outdoors single tank wings. I've used both the 34lb and 55lb single wings on several occasions. I much prefer a narrower wing like the OMS 32lb doughnut, any of the DSS wings, Halcyon, Oxycheq, etc.
Good luck!