[Elecraft] K2 and transverter best freq to use ?

[Carel, pc5m]

Hi,
 
As a new user/builder of K2 (waiting for the package to arrive...)  and
targetting the K2 to be used for 144 MHz and up contest operation (with huge
signals likely to be present) a question:
 
- What is the best frequency to use for transverter usage ? (the common
28MHz or 14MHz ?) considering the best IP3/Intermod and phasenoise behaviour
(on RX but also on TX !) ? . 
- What figures can be achieved at that frequency (IP3, phasenoise and
sensititvity) ? 
- Of course good IP3 and good sensitivity are not each others friend :-(
- Actually IP3 on VHF is not a "big" issue (not so many stations around) but
more the related RF blocking behaviour due to gain compression of RX stages
and reciprocal mixing due to phasenoise.
 
Maybe it is an "old" question, but couldn't find it in the archives and most
data available is for 28 MHz only.
 
Thanks in advance,
 
Carel, pc5m