For versatility, I would get the EU2000i. You can later parallel it with another EU2000i, EU1000i or even an EU3000is if you later decide you need to upgrade. The EU's will sync up with any other EU. As far as the Companion model, I would just buy a set of parallel cables, cut them in half, stick a junction box in the middle with a 30 amp receptacle. That will save you $100+ and is totally safe.