Excelent performance for Sonata! But Bankstone asked for life expectancy of Elantra's, not Sonata's, isn't it true?
I've got a friend who owns older Lantra RD 99 1,6l with 225.000 km (cca 150.000 miles). He doesn't drive his Lantra as formula pilot and changing all parts as necessity. Most filters,liquids,sparks,brake pads. He never changed entire 1,6l engine, although he had some not so cheap service faults. Especially clutch and neverending timig/drive belt changing after every cca 75.000 km. Already older Lantra's have fully galvanized upper body, so huge corrosion appears only on chassis and around wheel corners.
I agree too, Sonata's are probably the most following Hyundai car through. More than E(L)antra's,Accent's and XG's/Grandieur's.
New Elantra 200x is better than older Lantra's, so go for it! And increase this Hyundai forum.
PS: brand new 1,6l engine for older Lantra's 99-00 costs 85.000,- CZK in my country (=cca 3.800,- $ now). New CVVT Elantra's engines will be expensive