I had the Magic Bullet and IMO it isn't built for long term use. Seemed to fall apart about 2 months after purchase.
Now the VitaMix is worth it's weight in gold for endurance and performance (my friend has one).
I don't know about the HealthMaster but it appears more like the VitaMix in construction. Go on Amazon.com and punch it in and see all the reviews there. Someone said that the ball bearings gave out in 2 months in the HealthMaster but someone else said the company stands behind it's product and so on and so forth.
There was a comment about the Bullet at what a joke it is and I have to agree.
So.....VitaMix or HealthMaster; You pay for what you get. I know they are both expensive but in the long run you want something that's going to last.
Look up the warranties on them and see what's up and then decide. If it's just for smoothies I would go with the cheaper option, but if you are going to be doing some serious blending then you might want to consider the pricey option.
Good luck