Integrity is always a good choice - especially when it it biblical integrity. That is what we learn from today's proverb. It is the integrity of the upright that will guide them. The word integrity here in the Hebrew has a strong emphasis on moral integrity. As always, when we read of morals we need to remember the moral law of God as the path that is set before us. These godly morals will "guide" us. The word used here is "nahah" and it means to be led or guided in the right direction or the proper path.
Think about the moral law of God. If we were to follow the 10 commandments in our everyday lives - not just the outward sins involved - but even the inward thinking Jesus exposes in the sermon on the mount (Matthew 5-7) - how often would we be guided into the very decision that was right and best. Not all of these decisions would be easy. Some would be painfully difficult at first - but all of them would be right - and would take us in the right direction in life.
The treacherous have no such guarantee. These are the peopl who act as traitors, they are unfaithful and betray others. The key relationships where this word is used is in regard to God's covenant (which includes the moral law) and in regard to marriage. These are people who make promises - but do not keep them. They enter into contracts but look for the loophole. We are warned that it is the crookedness of these people that will destroy them. Crookedness refers to the perversions and deceitfulness that governs their actions. They are distorted and perverse in their character and thinking - and that is why they are treacherous in their dealings. What is so dangerous for us in this is that the treacherous seem to do well for themselves initially. They seem to prosper and have pleasure and fun at the start of their crooked choices. But wait and be patient. The best friend of truth is time. Eventually you will watch the house of cards the treacherous build come crashing to the ground. They are caught in their adultery. They are exposed in their perverse dealings. Their ponzi schemes implode. Their crooked financial dealings come to light. Then you see the wisdom of this proverb. Indeed the crookedness of these people destroy them - and all the while the upright, guided by their integrity and moral uprightness - are guided safely through.