What Triumph are you interested in?
I bought my TT new in 00'. Put money down before I'd even seen one. Haven't had any regrets since. There were a couple recalls (clutch cable, sidestand bolts, sprag clutch bolts) but beyond that the bike has been utterly reliable. I currently have 17,000 miles with NO problems. Although the TT has been discontinued, the Daytona 600 is basically a re-vamped TT and as such has benefited from 4 years and one race season of developement. As was mentioned above, a Daytona 600 won at the Isle of Man in 2003.
The Speed 4 basically trounces the other contenders in the naked 600 field (Honda 599, Yamaha FZ 600). Better brakes, fully adjustable suspension, stronger acceleration, etc. all for less than the Honda and the same price as the Yamaha. It is not a beginner friendly bike - it's basically a TT with no fairing.
The Daytona 955i can't be directly compared to the Japanese liter bikes. It uses a 3 cylinder motor compared to the Japanese 4's, and a single-sided swingarm compared to the conventional units on the Japanese bikes. It blends the torque of a twin with the top end rush of a 4, has a beautiful exhaust note, and makes an excellent street bike. The ergonomics are friendlier than those of the Japanese literbikes - more street oriented than track oriented. It'll still cook - quarter mile times are in the low 10's.
Best part about owning a Triumph is that you don't see "your" bike on every corner. I have yet to see a Daytona 600 on the road. I have NEVER encountered another 00' black/yellow TT in the 4 years I have been riding mine.
Sportbikes these days are separated by just a few pounds and a few horsepower. Each DOES has a different personality and each has strengths and weaknesses. Sit on a few bikes, take a test ride (Triumph is generally pretty liberal about test rides), and pick whatever bike sends tingles down your spine.