Dang, If you asked me, those are more than what I would even think about buying... especially for glass tanks!!
Best bet for me is always 2nd hand!! That, the local advertisments, eBay, or wait for a friendly neighborhood PF'er to get rid of one. I paid $150 for my 125 gal from a friend, and recently got a 35 gal off Craigslist.com for $20. All acrylic, too!!
They're all 2nd hand, but what matters most is the predetors inside the tank!! (And thats what Im putting most of my investments in)