Yes, all Malibu's quoted boat weights are 'optimistic'. The Pro Explorer is more in the 23-24 kg range I reckon.
The X-Factor is one of the heavier boats on the market it's true, but please note that they are a BIG boat compared to Prowlers, Scuppers etc. After all, they do have a carrying capacity of 270kg compared to the P13's 180-200kg & the Scupper's 160kg.