i use 81+ XPA-5 also~~
the 12V trigger is running very good~~~
but the xpa-5 power seem not powerful as my expected~
i was use 81 with a NAD int amp 100WX2...when i watch "The Dark Knight" was using -15dB...
but now use XPA-5 watch the same movie... using -8dB....
81 is 140W per ch~
XPA-5 can show more details but seen not powerful enough??
maybe XPA-5 not yet run in ...coz i am using new diy power cord....
so the performance is not like 200w per ch???