Hi, I was just reading the eXmark catalog and was curious as to what this meant: They say the Lazer XP uses a Unitized, tubular frame design which minimizes vibration, enhances stability and extends product life. Is this something different from the other regular Lazer frames? Explain please...... They also say the XP uses a unique dynafocal engine iso-mount system which dramatically reduces vibration. What exactly is this? Thanx a bunch!!!