Heres the situation. I am considering both of these cars. I am very turned off by the fear of a transmission failure in the C43 which is basically the only reason I have decided not to purchase it. Are these fears unfounded? I have only owned BMW's and have never had a benz, but have driven the C43 and love it (granted, I love the 540 too). What are your opinions?

They aren't in the same league. The 540i is a luxury medium-class sedan, comparable to the E500. The C43 is an uber-fast small sedan, comparable to the M3. The 540i is more luxurious, comfortable, and prestigous. The C43 is more fun to drive, and moves very quickly.

Yes and no. I understand they are different cars, and different markets, however these are the two I am considering and was asking for opinions on that. I realize that the C43 is a sportier smaller sedan. On the other hand, they both have ~300 hp V8s and are separated by only 200 lbs.

Horsepower and weight aren't the only two factors to consider. If you want relevant performance numbers, look at the 0-60 and 1/4 mile times.

if u r worried about the tranny, just make sure it has been replaced and/or the software revised (i think that was part of the problem).

1/4 miles..generally..a manual 540i Sport will be half a sec faster... auto 540i Sport and auto C43 will be identical. if u need, i'll use just one magazine..manual 540i 14.0@101.7, auto c43 14.4@99.0, auto 540i (wagon tho) 14.4@95.6

i just saw an automatic 1998 540i dyno between 238.4 hp and 238.9 hp in three consecutive pulls. 15% tranny loss. very impressive.

i think it's a tossup between the two. c43 will be smaller, 540i larger...so it may be more advantageous whether or not u carry more passengers often. both cost about the same when new.. u should try and test drive more. either way, i don't think u'd lose out.. if u like manual trannies...540i is the only way to go. but if not, then ...tough choice..

ive owned both... i enjoyed the c43 more... it has a sportier feel and more exclusivity. and i really wouldnt worry about transmission issues as long as you have it serviced every once in a while. the 540 is good if you are a family man cause of the additional size, but its overall mass production and heftyness just wasnt for me. and despite car magazine numbers, i have beaten every 540 i have come across in my c36 and c43... its always close, but the amgs always won.

Of course that's becuase it's an AMG.