const QByteArray SEP = ": ";
const QByteArray NEWLINE = "\r\n";

QMap<QString, QString> m_Values;

void QAmiPropertyMap::convertStr(const QByteArray &str)
{
    int indexNL = -NEWLINE.count();
    while(indexNL != -1) {
        indexNL += NEWLINE.count();
        int currStart = indexNL;
        indexNL = str.indexOf(NEWLINE, indexNL+1);

        QByteArray s = str.mid(currStart, indexNL - currStart);
        //qDebug() << s;
        int cutAt = s.indexOf(SEP);
        if(cutAt == -1)
            cutAt = s.count() -1;

        QByteArray key = s.left(cutAt);
        QByteArray value = s.right(s.length() - cutAt - SEP.length());
        //qDebug("KEY: %15s\tVALUE: %15s\tCUTAT: %d", key.constData(), value.constData(), cutAt);
        m_Values.insert(key, value);
    }
}

Elapsed time:    519 ms
One cycle:   1.730000 ms
Create item:     0.008009 ms
Items:      216
Create count (300x216): 64800