The problem is that most people do not know the quality of a converted chainsaw or weed whacker engine, They have a lower opinion of them because they are converted engines.

Some of the best RC engines out there are from conversions and last forever if treated right.

Here is a perfect example of that.
http://www.rcuniverse.com/market/item.cfm?itemId=837350

It is a Brilleli 46cc engine that is a Poland chain saw conversion that you used to could buy the whole chain saw for about $125.00

If the engine has not been damaged you will not find a better engine for the money,

Milton