RFC3339 DateTime struct for C#

RFC3339DateTime.cs

public struct RFC3339DateTime : IEquatable<RFC3339DateTime>, IComparable<RFC3339DateTime>
{
    private readonly DateTimeOffset _value;

    private static readonly string[] _formats = new string[] { "yyyy-MM-ddTHH:mm:ssK", "yyyy-MM-ddTHH:mm:ss.ffK", "yyyy-MM-ddTHH:mm:ssZ", "yyyy-MM-ddTHH:mm:ss.ffZ" };

    public RFC3339DateTime(string rfc3339FormattedDateTime)
    {
        DateTimeOffset tmp;
        if (!DateTimeOffset.TryParseExact(rfc3339FormattedDateTime, _formats, System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.AssumeUniversal, out tmp))
        {
            throw new ArgumentException("Value is not in proper RFC3339 format", "rfc3339FormattedDateTime");
        }
        _value = tmp;
    }

    public static explicit operator RFC3339DateTime(string rfc3339FormattedDateTime)
    {
        return new RFC3339DateTime(rfc3339FormattedDateTime);
    }

    public override int GetHashCode()
    {
        return _value.GetHashCode();
    }

    public override bool Equals(object obj)
    {
        if (obj == null) return false;
        if (!(obj is RFC3339DateTime)) return false;
        return this._value.Equals(((RFC3339DateTime)obj)._value);
    }

    public bool Equals(RFC3339DateTime other)
    {
        return this._value.Equals(other._value);
    }

    public static bool operator ==(RFC3339DateTime a, RFC3339DateTime b)
    {
        return a._value == b._value;
    }

    public static bool operator !=(RFC3339DateTime a, RFC3339DateTime b)
    {
        return a._value != b._value;
    }

    public int CompareTo(RFC3339DateTime other)
    {
        return this._value.CompareTo(other._value);
    }
}