I am pretty close to signing with a contractor for a geo system. However, the only part of his quote that is not better than the other three I got is the well guarantee. The others are 30 or 50 years and the well driller on the strongest quote is two years. I called today and got some clarification - the well(s) are guaranteed against collapse for two years and the tubing is guaranteed for 50 years. Does this sound like the standard for geo systems or should I beware.