DeWalt XRP is just a battery. It stands for "Extended Run-Time
Performance" It just means it has a longer lasting battery, not
that it's really more powerful, but the good batteries are
generally put on the better DeWalt tools. The voltage of the
battery is going to be the major limit to how much power it has.
The advantage of the LXT tools is the power to weight ratio the LXT
is 18 volt with the weight of 12 volt tools. Its not more powerful
in over all power but it is more powerful for its weight class.