I think most places are still open - It's September where they really shut down I believe. We've never been in August though.
It is true that the flybridge is great on the 48. Haven't been on the 48 power cat, but have been on their 58 Sail and that too had a huge flybridge. We did make a lot of use out of it.
It is nice though when you are sailing along and just hear the water rushing along. There's still plenty of places to hang out - trampoline, forward cockpit or the rear seating area. Powercat just gives you one more option. The only other big plus is that I believe it has an electric grill - 58 had this too and we loved it.
With only 5 of you plus skipper, you'll have plenty of room regardless. So it's really all about preference.
With the Sail Cats, there's also an owners version - The Skipper would then take the crew cabin and you could take the owners side and let the 3 kids share the 2 other cabins.
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