Like you I always wanted the Triumph cruiser but couldn't afford it. Like you I have been lurking on this site since '05 (see my membership date) and like you I got the 650 V-star instead (an '04) - which I really liked (gutted pipes, rejetted & K&N pods). It had enough power and handled well and has a great reputation.
This year I could finally justify the extra cash for the America. 60% more power - handles better - less vibration - better build quality - and apparently a longer lasting motor which is saying something cos the V-Star is legendary for it's rock solid reliable motor.
With the V-Star I would often go for a 6th gear on the slab - the high revs of cruising at that speed were tiring. In comparison the America/Speedmaster has that gear available. And you can easily switch from the 18 tooth to a 19 tooth front sprocket to drop your cruising revs about 3-400 for the same cruising speed. The drive shaft of the V-Star was great for low maintenance but you were stuck with the gearing.
The only downside in comparison that I have found is the V-Star has a lower center of gravity and coupled with the gearing and drive shaft it makes for easier very slow speed tight turning. I am still a little awkward at very slow speed on the America. I imagine that it is mostly a case of getting used to the gearing, riding the clutch more and feathering the rear brake.
Even with that slight negative I am still utterly sold on the Triumph.
As a reference I commute daily on suburban roads and cruise the slab and twisties for recreation. I weigh about 180lbs and am fairly aggressive in my riding style.
