I'd think that the Whacker packer would do a better job of compacting the clay, provided it was laid down in small enough lifts. But, the downside is that it'd probably take more time to do it.

I wish one of the dirt guys would chime in!

www.hoosierpondpros.com

[Linked Image from lh6.ggpht.com]
http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).