I would go ahead and use it for this weekend! Unless you NEED to measure out .05 ounces of hops, it will be accurate enough to do your brew. I mean, if you are SURE you will hit X gravity, and Y volumes, then you MIGHT need to worry about .05 ounces, but chances are , you will not be that close, or the recipe will not be that unforgiving.
Those small numbers are usually only a problem if you KNOW what you are goign to get for wort, and if you are brewing either a very small batch, or brewing a very hop-light beer.