There are actually many different cats that are good or great bluewater cruisers. Some fall into the light and fast like the Gunboats, others are heavy and slow like the older prouts, and many in between. Our cat Makai is a maixm/voyage 380 and is a great cruiser. We have put many miles under the keels.
The issue is not which one is best, almost everyone has an opinion on that, but which is the best for your given tastes and circumstances. Some like light and fast, boards or mini keels, etc.... We happen to like the quality and sailing abilty of the Voyage line.
You say you don't have experience of ocean passages. I would recommend getting the experince by sailing on as many different boats as possible to determine what you like and want. I have been sailing for over 30 years but Makai is my first cruising cat. Although it is a great boat and we love it, but we decided we want something bigger (other than that we love the layout and setup). This is a direct result of our experinces. The point is if you are looking to buy the end all as your first boat the learning
curve may show you that it wasn't your best choice and something different (our case bigger) would have been better. Most peoples budget
can't take a second boat purchase
Though if we decide we can't handle shoreside to much longer we will load Makai and head