Here's a quick run down of the main differences between them, as well as the advantages and disadvantages of each:
The Magna is lighter and more comfortable, while the Tracker has a thicker outsole and more protective overlays. The Tracker also has a waterproof membrane, while the Magna is only water resistant. This means the Tracker Forest ESC are more robust, and suggests they will last longer with the extra stitching.
The Tracker Forest ESC are waterproof, however, there is some moisture getting through after a long hike in wet conditions. Many, including me, recommend waxing the shoes. I'd highly recommend Nikwax leather care products and that your order this - Obenauf's Heavy Duty LP Leather Preservative - a heavy-duty wax developed by a wildland firefighter in Idaho to protect his boots against water, fire retardant chemicals, heat, ash, abrasion, etc. Trust me, it's good enough.
Winter is here and you know that means wet snow and chilly temperatures. If you're looking to upgrade your winter footwear, you may be considering the Vivobarefoot Magna or Tracker Forest ESC boots. Both of these boots are designed to keep your feet warm and dry in winter weather, and they each have their own unique features to offer.