We have a Blendtec (and the specialty twister jar, which is a big help for thick things like hummus, peanut butter, etc). Either the Blendtec or a Vitamix will be a huge advantage over a standard blender - of course, this depends greatly on what you want to use it for, and how often. My wife and I thought it would be crazy to spend $400 for a blender, but then we borrowed a friend's for a week.
You can achieve similar consistency/results with a lower end model, but there are two main reasons we went with a high end: processing time and cleanup. What would take me 5+ minutes in an Oster, we can do in 30 seconds or less in the Blendtec. Cleaning is very, very easy, and important for us. If it's hard to clean well, that's a major barrier to use, especially when strapped for time. Cleaning is the big reason we chose the Blendtec over the Vitamix. Blendtec uses a dull blade design whereas the Vitamix uses a sharp blade. For the times when a simple rinse/blend with soap and water isn't enough, I don't worry about slicing my hand with the Blendtec.
The Blendtec has an LED counter on the front to show the minutes used. We bough ours in Nov 2013. We're currently at a bit over 1100 minutes, so we use it on average about 2 minutes a day. We have limited counter space. The Blendtec and the coffee maker are the only appliances that sit out.
If you can borrow from a friend to test any of those models out, I'd highly recommend it if you're not familiar with them.