Both the Malibu Response LXi SE 2007 and the Malibu Sunsetter 23 XTi 2005 are modified-V designs, so the buying decision usually comes down to a handful of practical questions: how many people are you putting on the water, how far do you trailer, and what does your tow vehicle weigh?
On paper these two are close siblings in the size department - Malibu Response LXi SE 2007 at 20,0 ft versus Malibu Sunsetter 23 XTi 2005 at 23,0 ft. Weight tells a clearer story for trailering families: the Malibu Sunsetter 23 XTi 2005 tips the scales at 3 600 lbs - 800 lbs less than the Malibu Response LXi SE 2007 at 2 800 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.
Both boats share a closely matched power ceiling - 400 hp for the Malibu Response LXi SE 2007 and 400 hp for the Malibu Sunsetter 23 XTi 2005. Real-world performance will come down more to which motor is actually bolted on, its load at the time, and whether it's a 4-stroke or 2-stroke setup. Fuel capacity breaks the other way: the Malibu Sunsetter 23 XTi 2005 carries 47 gallons versus 41 gallons in the Malibu Response LXi SE 2007. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.
For family outings this is probably the sharpest distinction between the two. The Malibu Sunsetter 23 XTi 2005 is rated for 14 passengers, while the Malibu Response LXi SE 2007 caps at 8. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Malibu Sunsetter 23 XTi 2005 could be the deciding factor.
Bottom line: Choose the Malibu Sunsetter 23 XTi 2005 if your priority is putting more people on the water - it handles 14 passengers and at 23,0 ft it has the deck room to back that rating up comfortably. The Malibu Response LXi SE 2007 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 8 that costs less to run day-to-day.