I used to fly both the 402C and the 404. From what I remember the power-to-weight ratio at MTOM was better on the 402C.
We had the last 404 ever made and that thing was a real dog on one engine, as if it hadn't been riveted together 100% correctly or something. You could not get book figures on the single-engine climb with everything done right.
One day I departed a short strip with a full load on a hot afternoon when the hose from the turbocharger (incorrectly installed) popped off the intake. Luckily this happened at about 8 thousand feet. With all that alitude in hand I tried a bit of trouble-shooting but the airspeed was unwinding, followed by the altitude so that I just feathered the engine. Then I got to thinking what this might have been and got it re-started, when it was not responding in the same way to the throttle as the good engine but still producing useful power when it was leaned way back.
Obviously, when that hose came off I lost the turbo-charging with the mixture still so rich so that the engine cut. If I had thought to pull back the mixture then I would't have lost the engine in the first place but that one is not in the book.
If I had lost that hose right after lift-off then I think I would have had a bad crash. Look at the graphs for a windmilling engine with the gear down and I think you will see something like -300 fpm! You would have very little time to get yourself sorted out before running out of altitude, no matter how good you think you are.
When I got back to base the muppet who had put the hose on incorrectly just shrugged and told me that all I would have had to do was lean it out, so what was my problem? I literally "saw red" for a moment!
Between the two I would go for a 402C. It flies a little nicer than the 404 and the engines are not as sensitive, Continental TSIO-520, 325 horsepower versus GTSIO-520E, 375 horsepower on the 404. I think the nominal TBO is 1,600 hours on the 404 and about 2,000 on the 402C.
What about the turbine-powered version of the 404, the Rheims 406? I would much rather trust my life to PT6 engines plus it burns Jet A.
Up-market a bit is the Cessna 441. One of those with -10 engines will hit about 290 knots burning ridiculously little fuel, something like 400 lb/hr. It has the same basic wing as the 404 and it flies very nicely too.
What do you plan to use the aircraft for, anyway?