Hi there, BSS DI ( Broken Syren System, made un UK) boxes are probably the best on the market, they offer road resistance and affidability; maybe the more expensive but the most reliable. Anothere good brand is SVC ( France. But I reccomend BSS also because they are easy to buy and sell second hand. You should get active DI boxes and avoid cheap brands because they don't last long on the road.

(that wasn't me!!!It was my dad,I got him on the keyboard.I suggest you trust him.Lena)