All elliptical machines perform the same function. I would say the best ones are the ones that you find that are the most expensive because they likely have the best durability and can sustain the most weight.
Four highly reviewed elliptical machines (according to consumersearch.com) are the Sole E35, Nordic Track Autostrider 990 Pro, Schwinn 420 and the Precor EFX 5-33.
If you are wanting to purchase an elliptical training machine there are numerous websites providing reviews. One of the best review sites for these trainers is http://www.consumersearch.com/. You will find reviews for elliptical trainers listed under fitness and sports/elliptical trainers.
You can find some of the best elliptical machine reviews at topconsumerreviews.com/elliptical-trainers There are numerous brands and thoughtful reviews.
There are actually quite a few different online reviews regarding elliptical machines. A great review site that I found is http://products.howstuffworks.com/elliptical-machine-reviews.htm. The site has a lot of reviews and is open to consumers. Another great resource is www.consumerreports.org its very informative reviews are insightful.
According to Lance Armstrong, you get what you pay for when purchasing elliptical machines. I think a visit to his website would provide the information you need about purchasing elliptical machines: www.livestrong.com/.../380796-what-are-the-best-elliptical-machine
You can buy the best elliptical machines online from amazon.com, ebay.com or horizonfitness.com.
There are many great elliptical machines on the market currently. The best overall elliptical machine is the Precor EFX 5.33.
Reviews are always a good thing to investigate and so is the case with elliptical reviews. Elliptical reviews for 2012 are available at: www.thefitnessofficial.com/
The best places to buy an elliptical machine are Canadian Tire, Walmart, or Sears. Each of these stores have multiple elliptical models available at varying prices, and they can be purchased both online and in their brick and mortar store locations.
The best elliptical exercise machine on the market is currently the Sole E35. It has received rave reviews for combining durability, value and function.
The best way to find this information about a reputable elliptical machine would be to check the ratings and reviews online. Other sources would be to speak to a fitness trainer or at a gym.
The best place on the internet for reviews of fitness equipment, and elliptical trainers can be found at the web address found here: www.consumersearch.com/elliptical-trainers.