They have the same specs. The Sportee page says:
"Versatile for beginning paddlers who want to circumnavigate a lake or an advanced coastal kayaker who wants the ability to surf big waves and explore sea caves"
That fits the OP's bill.
I seem to recall Matt Broze telling me that Northwest did some of their manufacturing, and I also recall Northwest kayaks being one of the few (or only) other line on display in the Mariner shop in Seattle.
Needed research: Compare the date of Mariner's going out of business with the date of Northwest's introduction of the Sportee.
Free Standing Boat Racks
First Need Purifier
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