I run the Alpha S852 (orange) in my truggy and the Z852 in my buggy. My son is sponsored by Dynamite and runs the Dynamite Xpe in his truggy and buggy. I have had them both apart and the Dynamite is just like the Z852 not the red head. In my opinion the S852 is perfect in a truggy, awesome bottom end and great top end. The Xpe in my sons truggy runs very well also, he gets quite a few looks as it really rips on the top end.
I have not ran the red head yet, I have had one apart and did some measuring on the port timing etc. Just a little modding and it would rip as good as the Z852. I will probably run one in my buggy next year.

Rex