Windows Central reviewed the Microsoft Ergonomic Mouse
A quote from the article:
Are you looking for a Surface Precision Mouse on a budget? Perhaps the Microsoft Ergonomic Mouse is your answer.Microsoft Ergonomic Mouse Review
Microsoft has released a brand new ergonomic mouse that takes design cues from its premium Surface Precision Mouse and folds it into a package that costs half the price. If you've always been a fan of the Surface Precision Mouse's ergonomic design and rich feature-set, but couldn't justify its $99 price tag, the Microsoft Ergonomic Mouse is the next best thing.