Per Micheal Artindale:
http://www.mec.ca/Products/product_d...45524442503911
is simmular to the dry tops i am looking at. The dry bottom is not the
farmer john type, it is like a pair of trousers.

Gaskets are at the waist, neck, wrist and ankle openings. I think I have
seen a pair of bottoms that had attatched socks.

Looks to me like something that would keep one reasonably dry as
long as they stayed in the boat.

Come out of the boat, go through the rinse cycle a few times, I'd
bet a weeks pay it's gonna take on water - big time.

I use a one-piece bag suit for lake paddling.

One-piece mixed-mode (neo john bonded to bag top with PolarTec
shirt) for ocean/surf when the water's really cold.

For less-cold water, I use a regular farmer john with a dry top
like the one you linked to.

That combo will keep one dry for the first few moments of
immersion, but in the end it's wet. OTOH, the john is a wet
suit.... i.e. it's designed tb warm with a film of water under
it. The top? Like I said I don't wear it when the water's
really cold.... maybe down to the low fifties; then I go to the
one-piece solutions.
--
PeteCresswell