Brittany runs an SW2, very nice chassis, very adjustable. My favorite chassis, handsdown. She is currently in 5th place overall for the winter series, competing in the WARCRC club. I got my first look at an XRC chassis last weekend, it appears to be a good chassis as well. Both of these chassis are designed for TLT axles, but you should be able to make them work with WK axles, with some work.
Tubers are way cool, in my opinion, no body to worry about and look cool, but can be tougher to set up correctly, if you have no experience with crawlers.
We should get together one of these days and I can let you drive ours, to get a feel for how they work. I run a 2.2txt with a torsion chassis, no shocks or 4link. Drives different than the SW2, there are certain situations where one outperforms the other.