I'm no expert so I don't count for much, but I can at least share what I've learned through about three weeks of daily research on about a dozen websites and perusing three separate forums. It didn't work for me, but you could always check the used and refurbished market if you really don't want to spend that much money. There are many self-propelled mowers for much less than $400 new, but probably won't be as durable as the Honda or Toro. Of course, you only have 1/4 acre and unless you are mowing constantly, you could easily get many years of service off the lower end mowers. Just check out sears for all the various craftsman (some are MTD and some are husqvarna made) and husqvarna mowers. As I have seen others point out, if you put in the time and effort for maintenance, even junky mowers can have a reasonably long life. As far as Honda and Toro, I think it becomes a matter of personal preference. The Toro is running an old B&S flathead, while the Honda is a much more modern engine design so it may just be the choice of what type of engine you would rather have. The Honda will likely be smoother, quieter, and use a lot less fuel. The B&S is an ancient engine so it will be very familiar to work on if you ever have worked on engines before and parts are literally everywhere and dirt cheap because its been the same design for decades. Neither engine is commercial grade.
Here's one more consumer survey type site regarding brands. This, nor consumer reports can be taken as a be and end all word on mowers, but can be used as one more piece of the puzzle when deciding:
Ratings | J.D. Power
and the corresponding press release which gives some brief info on the numbers:
2011 Walk-Behind Lawn Mower Study | JDPower.com
Edit: Just to add, if you have a steep hill, you definitely need to go rear wheel drive as front wheel drive will likely lose traction. If you want to go cheaper, there is this craftsman model that is a CR best buy just for example. Its made by Husqvarna and uses the same engine as the Toro, but I would guess that the drive system is not as well made as the toro or honda:
http://www.sears.com/shc/s/p_10153_12605_07137435000P?prdNo=3&blockNo=3&blockType=G3
