Dear Ian, You are not alone!
We have 2 Leica (Jung) 1325 freezing microtomes. In well trained and
practiced hands they cut very good sections at around 4 microns.
We use them to cut fresh tissue frozen sections in private hospital
theatre suites around town. We cut parathyroids, thyroids, lymph nodes,
breast, etc. We fix the section after cutting, its hard to get good
sections of boiled tissue.
They are truly portable, not like some of the portable cryostats that
weigh 50+Kg.
But, if I had a choice I'd use a decent cryostat (eg. Leica CM1100 is a
bench top unit that cuts beautiful sections). 
Cutting with a freezing microtome and CO2 is definitely an art.
David.
David Taylor 
Laboratory Manager 
Drs King & Mower 
Adelaide, Australia