I own the mac 26s...I took her to the Bahamas this summer for 3 weeks... The crossing was worse that I wanted E 10-15 knots seas 4-5ft period 5sec. It was choppy and wet ride with the bow under water many times.
There's the point there. That weather would not bother any sailboat built to be on the ocean. But a Mac 26 is about 2,800 pounds, as opposed to say 5,000 pounds for a similar-size Bristol.
Want to know why the Mac is 2,200 pounds lighter? The hull and deck are much thinner and weaker. The bulkheads, if any, aren't strong. The rigging and other gear is undersized.
It's also a flat-bottomed boat, which means it pounds in any type of weather, exasperating the structural weakness.
Any boat can sail in nice weather. But I wouldn't want to be on that boat when a sudden Gulfstream thunderstorm kicks up and seas go up to 8-10 feet.
When the boat is inevitably knocked down in that storm, good luck on it righting itself anytime soon with that hull shape, even if the boat holds together.
When I sailed in Miami, I knew someone who sold a Mac 25 because he thought it wasn't seaworthy enough for Biscayne Bay, which can get rough.
But ... your boat, your life, your decision. At least buy a good life raft.