Starphire glass: a little softer, thus easier to scratch; far better clarity; no color shifting of what you see
Regular glass: harder, less expensive, adds a green hue to what you see.
I've had Starphire with my 280 for almost six years, and would never go back. The new tank is being made with the same. It takes a little more work to avoid scratching it, but compared to acrylic that's no big deal. Acrylic scratches if you just look at it wrong. I accidentally swiped my cleaning magnet across the angled acrylic tank in my foyer, snagged an Asterina starfish and proceeded to lay a swirly pattern all over the viewing panel. I was pretty incensed. However, I digress. This isn't an issue with Starphire, but metal blades or rusty scrapers can do damage so it is important to be careful. That's all I'm saying.
Just remember the tank is usually the cheapest part of the hobby, even if you spend more on your tank. [smilie=wink.gif]