Ironman treadmills are made by Keys Fitness Products, a company that offers two treadmill series: the new T-series and the classical M-series. They also offer an intermediate model called the Ironman Triad which combines characteristics from both models. The company is situated in the middle class of the manufacturing sector with prices ranging from bellow $1,000 to over $2,000. They have good models that are suitable for a normal program of exercises like the M2, M3, M4 and the T150, T220, T320 but they also provide larger and heavier machines that have an impressive stability and an extended number of controls.
From all Ironman treadmills, the Triad model is one of the most appreciated, it comes with a modern design like the T-series but it has the same accessories with the M5 which was a great machine. It's weight is under 400 lbs and it comes with a decent engine that generates 3hp. A maximum speed of 10 mph can be reached with this treadmill. It is true that the Triad model took much of its monitoring function from the M-class models but it didn't import all the features, so while the M models have a 12% inclination angle the Triad comes with a smaller angle of just 10%. The running surface of a Triad is larger that at the M6 so there are some here advantages too.
Ironman treadmills come with a good warranty: 10 years for the motor, lifetime for the frame, two years on the parts and 12 months on labor. The Ironman treadmills offer a good quality-cost relationship for their price when compared with the competition. If we compare the 320T model with the Smooth 5.25 that has a similar price you will realize that 320T comes with a bigger walking surface and more additional functions. However the Smooth model brings a better warranty, better ratings, a larger inclination angle, so it is really up to you to decide what suits you best.
Another thing to mention about the Ironman treadmills is that in the past they might have had some problems with the electronic system. Despite some controversies, the models are well appreciated by users so that most Amazon buyers give them 4 stars out of 5 which is not bad at all. If you decide to buy an Ironman treadmill don't run to the first sports shop because you probably won't get a sale, I advice you to take a look at the online promotions because there are increased chances to buy it much cheaper.