You don't gain a ton of room over the 38 due to the 3 engines. A little more of a cruiser look than I care for in the cabin. Slower than a 38 with same power and one less power plant. I like the 38 a lot but I would not even consider the 45.
If I wanted 43ft and above I would look at the Nortech or Black Thunder way before the 45ZX. Remember this is coming from a Donzi owner that thinks the ZX line is great.