Small Engines (Lawn Mowers, etc.): Briggs&Stratton Recommended Gasoline, craftsman lawn tractor, briggs stratton

Question
I recently had a Sears repair man out to make minor adjustments on my new Craftsman lawn tractor.  The engine is a Briggs&Stratton INTEK OHV 17 hp.  He recommended not using Walmart and several other gasolines because they had additive's that had a stickiness that damaged the valves.  Have you ever heard anything like this ?

Answer
That's sort of the reason.  Discount gasolines use cheap oxygenators which are largely ethanol.  Ethanol is very bad for small engines.  Many States now require E-10 gas, 10% ethanol, and the carburetor replacement numbers have gone through the roof.  

Chevron seems to be the favored choice for boat usage.  The Techron additive can also be bought in bottles and added to your regular fuel.

I only use BP and have had good results.  But your location will have a big impact on your gas quality.  Certain areas have specific regulations about gas formulation and this makes performance very spotty.

Your best bet is to simply use something like Techron or SeaFoam in your lawnmower gas at all times.  Never store the mower for longer than 3 weeks with gas in it and never use gas that's been in a can for longer than 3 weeks.  This will preven most fuel related problems.