1.8L I-4 HEV 134 hp (Prius)

+ Monumental technological achievement

- Takes the fun out of driving

= Benchmark efficiency

2.5L I-4 179 hp (Camry)

+ Does its job

- Not as impressive as big-brother 2.7L

= Tastes like chicken

3.5L DI V-6 306 hp (Lexus IS 350)

+ Sophisticated fuel injection strategy

- No one needs both belt and suspenders

= Evolution has stalled

3.5L V-6 275 hp (Lexus RX 350)

+ Competent, quiet, high-volume V-6

- Tiny improvement over four years

= Competent but dull

3.5L V-6 HEV 295 hp (Lexus RX 450h)

+ Exhaust-heat recovery system quickens warmup

- Hard to quantify gain over last RX hybrid

= More tortoise than hare

4.6L V-8 310 hp (Tundra)

+ Nice to see focus on smaller V-8

- Trip computer lacks MPG calculator

= Fine effort