The spec sheets list the Malibu Sunsetter LXi 2006 as modified vee and the Malibu Wakesetter VTX 2008 as v25 wake (cut diamond optional), so check how each hull rides in the conditions you use before you decide.
On paper these two are close siblings in the size department - Malibu Sunsetter LXi 2006 at 21,0 ft versus Malibu Wakesetter VTX 2008 at 20,0 ft. At 3 300 lbs and 3 300 lbs respectively, both sit in a similar weight class - either should pair comfortably with most mid-size SUVs and half-ton trucks, though always confirm your specific tow rating with the motor added.
Both boats share a closely matched power ceiling - 400 hp for the Malibu Sunsetter LXi 2006 and 400 hp for the Malibu Wakesetter VTX 2008. 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. Both carry nearly identical fuel loads - 46 gal and 46 gal - so range won't be a tiebreaker here.
For family outings this is probably the sharpest distinction between the two. The Malibu Sunsetter LXi 2006 is rated for 12 passengers, while the Malibu Wakesetter VTX 2008 caps at 10. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Malibu Sunsetter LXi 2006 could be the deciding factor.
Bottom line: Choose the Malibu Sunsetter LXi 2006 if your priority is putting more people on the water - it handles 12 passengers and at 21,0 ft it has the deck room to back that rating up comfortably. The Malibu Wakesetter VTX 2008 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 10 that costs less to run day-to-day.