I think you've enumerated the choices and their
drawbacks very well.
A couple others in the field are:
o OHR 100A - http://www.ohr.com/ohr100a.htm
o Emtech NW30 http://emtech.steadynet.com/nw.shtml
The Emtech is no longer available with an enclosure.
Alot depends on your building experience.
For a first QRP kit, I don't think you could go
wrong with the SST, the SW+, or the MFJ Cub.
The other transceiver kits mentioned are a bit
more complex, and may be a better "second
QRP transceiver kit".
Replacing one or two capacitors with NP0s
reduces much of the drift in the MFJ Cub.
The ARRL has a package deal on the 40 meter MFJ
Cub kit with Rich Arland's QRP book at:http://www.arrl.org/catalog/?item=1042K
I bought my MFJ 9315K kit from WB0W. They
had a nice discount on these.
I usually suggest beginning with a 40 meter
kit, as there is almost always some activity on
During mornings, I've sometimes found 30m empty
of signals. Most 30m activity occurs during the
late afternoon and evening.
The QRP contests, like the Spartan Sprints,
'Flight of the Bumblebees', and 'QRP to the Field',
are alot of fun, but you won't be able to play
in them with just a 30 meter rig.
It is alot easier to work DX on 30m than on 40m
though, and if your main HF rig doesn't have 30m,
that would certainly be a reason to begin with a
30m QRP transceiver kit instead.
Hope this helps, and have fun!