Rating for exchanges

How do you rate swaps on the 5 star system? What would it take to be less than 5 stars?

Is there any standard what 5, 4, 3, 2, 1 or 0 stars would take to get them?

Well I would say that depends on both the circumstances and your personal approach.
5 means "perfect", there are no more than 5 stars to give
4 could mean, almost perfect with - let's say - a coin missing or wrong, or bad packing or long waiting times, unfriendly or unreliable contact etc.
3 could mean a combination of both or more points from above
2 well - could mean even worse, lots of missing coins, unfriendlyness etc.
1 seems to be worst case - no coins received but at least friendly?
0 no coins received - most obviously a cheater. meant as a warning: "don't trust this guy"
this is how I handle this

Here's how I use the rating system:

0)  Warning!  Do not trade with this user!
1)  This trade had problems, and I will not trade with this user again.
2)  This trade had problems, but I would trade with this user again.
3)  I am satisfied with this one trade, but I would not trade with this user again.
4)  I am satisfied with this trade, and I would trade with this user again.
5)  There was absolutely nothing that could have improved this trade further.  All the coins were hand-delivered in Mint condition with an extra gold ingot included!

Once upon a time I made a purchase on eBay, it went well. So I bought a second item from the same dealer on eBay. That item never arrived, so I made the mistake of stating so publicly on eBay. The dealer gave me a negative buyer rating, which, as it was my first rating and only rating, means I can never buy or sell on eBay as I have a minus trade rating. I learned a valuable lesson from that incident "never criticise, condemn or complain"

Matt

More thoughts on the trade rating system:

I don't think there's any shame to be had in receiving a 4... it's still above average, if you consider the average to be a three.  If the average is a five, how can I tell the community that this member is above average?

I don't give out fives because a "perfect score" of 5 should be rare and hard to earn.  Giving every trade a 5 by default doesn't leave any room for improvement.  If I later develop a better packaging method, my score cannot improve.  

I also think that a rating system populated by nothing but 5s takes meaning and significance away from the rating statistic.  There are five (or six) rating levels... use them all or reduce it to a simpler system.  (EDIT: To illustrate my point, look at eBay.  I find it stupid that even a bad rating for eBay sellers is over 90%.)