MBtex and Artico are Mercedes artificial leather (vinyl) coverings. MBtex (no longer offered) was virtually bomb-proof, hard as armour and fitted to all taxis. The modern equivalent is Artico, much more realistic looking and feeling but no where near as robust or long lasting as MBtex, or genuine leather come to that. Many instances of split bolsters within the first couple of years of use.
All modern automotive leathers are PU coated (sealed) and I'd be very surprised if Lexus leather is any different. Lexus models sold in the USA come with vinyl as standard, leather being a cost option.
Lexus leather is infinitely more luxurious compared with the standard option MB leather, possibly on an par with their Passion leather, I just hope it is equally robust...