I had a 86 300E which was my first Bnez, I loved everything about it. About a year ago my 300E was totalled. I couldn't decide which car to replace the 300E, finally I decided to get the 94 E420. You will get better performance on the E420 but not by much. The 300E is a very capable car on the streets. Every time you puch on it. you'll get instant acceleration. With the E420, you don't want to race on the streets. They are both different animals. Like an earlier post states, the 6 cylinder revs higher. A good example between the two car when be making the light in an intwersection when the light is yellow. The 300E that I had will always make the light, but with the E420 the light turns red before my car can completely cross it. Don't get me wrong the E420 is not slower, but in certain situations the 300E is faster. The E420 rear differential is geared for better fuel economy that is why I think it's slower on the streets . On the freeway the E420 will eat up the 300E. The perfect car for both street and highway performance would be the 500E. Overall I like the E420 better because of the fuel economy and the power it has on the highway over the 300E. Use the E420 for commuting and my 97 S500 on weekends. the S500 is faster then the E420 even though it's a lot heavier, but the fuel economy sucks. So to answer your question, get the E420, repairs will cost more but hey it's a Benz. There are no cheap Benzs. Oh yeah, if you feel that you need more performance on the streets, just change the rear differentials for better street performance. Ther are a few people that have gone that route here in this forum.