I like the look of the Arrows too but only the Full. The s/o look too fat. The taped end caps on the full vs s/o is a small amount of detail but makes it look so much better.
It sounds meaner too but then again, it comes down to engine management. You could bolt up the Arrow with the stock ecu but any tuning, you're going to have to get either a DP, Nemesis, Microtec etc.
The headers. Currently Termignoni sells the header kit/ecu for $1799. The new ones are more expensive so hopefully they cleaned up the welds!