We had one of those - best caravan we ever had, especially if like me you are over 6ft!
The water ingress issue in the front side lockers was due to poorly fitted/sealed grab handles on the front letting water get in. They resurfaced the locker floors (remove the trays) under warranty. We also had a small amount of wetness but not actually rotting on the outside of the offside underfloor right at the front. Again that was resurfaced under warranty. It was suggested that water spray from the car could have contributed so we fitted hefty mudflaps which stopped it.
The only other issue we had was that the Alu-Tech body can distort slightly if the caravan gets hot outside and it is not set up exactly level. The result was that we couldn't open the door from the outside but we could from the inside. Our dealer put is right on that one: the internal handle pulls the catch back further than the outside handle BUT if you turn the lock from the outside using the key it will also pull the catch further back. The body distortion on that occasion (at CMC site Sandringham) also made the glass lid on the cooker foul the bottom of the cupboards above it, but it corrected itself when the body cooled down overnight.
We found out the hard way that the noseweight with the van empty is well over 100kg. We bought some Really Useful boxes (that happened to be exactly the right size,) put our cleaning materials and spare bedding in them and put them inside the wardrobe in the bathroom. Balanced the van at 84kg noseweight and never suffered any tail wag.
Had that van six years it having been two years old when we bought it. Loved it, and a much better van than the Unicorn 4 Seville that we bought new to replace it.