Depends on what you're after. For me it was a logical upgrade - the added isolation and ability to switch cables so I could wear them over ear. I personally (for my taste) think it is a sonic upgrade as well. But its an incremental upgrade from the T1 - not a major upgrade. Whether that is worth it is something only you can answer
Headphone Reviews and Discussion - Head-Fi.org
One Question for ya is this...I have the Titan1, should I get the the T5 also or just too close a sound sig?