Nearly all of the mowers mentioned, with the specific exception of the John Deere, are made by one company: MTD. The home page at the link lists about half of the "brands" (that I know of) that they actually produce.

The design is basically the same for all of them, although the various retailers may select minor "special features." Some retailers get a thicker coat of paint, or chose to offer only the hydraulic transmissions, etc; but otherwise there's not really too much reason to pick one over another except based on price and after-purchase support. Note that the lowest prices may be "unassembled," and the assembly fee may be more than the difference for one that comes all put together.

Most of MTD mowers use Briggs & Stratton engines, although a few models have Tecumseh or Kohler. No problems that I've heard of specific to any of the common engine makers. In most cases, something else will wear out before the engine.

Retailers may occasionally go to another maker, sometimes just for one or two models; and Sears is one that has done that, often putting the "Sears brand" on side by side models made be different manufacturers. There really aren't too many other places they can go though, and you may have a hard time finding out who makes a given model until you get the warranty papers at delivery time. With Sears, you may never know, since they'll have Sears part numbers for everything - regardless of who made it.

If you really don't want an MTD mower, you almost have to go with one of the heavy duty jobs, or one of the several ZTR (zero turn radius) machines.

John Deere has an excellent reputation, and every one wants one, even if just for the "guy thing" factor. Unfortunately a "Deere" is usually priced at 1.5 to 2.0 times similar models with other brand names. It may actually be worth the difference, but I've never been able to afford one to try it out.

Basic Decision 1:

With a 1.5 acre yard, you might want to consider a "garden tractor" with mower attachment, rather than just a mower. There is a substantial difference if you might want to tow a cart or maybe put a snow blower on to clear the drive. The typical mower may be dressed up to look like a tractor, but its "pulling power" will be near zero.

Basic decision 2:

Be sure to do a little checking on the widths of your gates and the gaps between trees and curbings. If your mower won't fit through even one of them, you'll wish you'd noticed it before you paid your money.

Most common mistake:

Some retailers order extra large engines to impress the buyers. Oversized engines are not an advantage and generally just tear up the drive train significantly faster - a very common cause of poor performance complaints. Get an engine big enough for the mower it's hung on, but avoid one that's significantly bigger than comparable models, unless the mower/tractor it's on is specifically designed to handle the extra HP and your intended use justifies the heftier design.

John