These are extremely well made engines. I bit heavy, but sturdy.
I have a few. Three of them have PDP, all have Perry carbs.
Here are links to my .21 PDP and .40 PDP tests:
http://www.rcuniverse.com/forum/m_8242211/tm.htm
http://www.rcuniverse.com/forum/m_8175602/tm.htm
David