[Aaronnc]

When people think of JD being "entry-level", or "residential" this guy sums it up best (granted this was posted in '04):

Starting at the front:

The Scag uses all taipered roller bearings, in the front wheel pivots and even in the caster wheels, Deere has lighter duty straight rollers in wheels.

Scags front caster arms are easily removed [two bolts]for repair or replacement, Deere is welded on .

Scag has a double tube "boxed" welded frame - probably the strongest in the industry, Deere is a single tube frame. Frame stiffness has a great deal to do with hillside stability and traction.

Scag has a larger floor pan area and the seat will roll back far enough that even a 6 ft 5 in guy can stretch his legs out and be comfortable, Deere is much more restricted.

The deck lift pedal is much easier to use and requires less effort on the Scag.

Both Scag and Deere make their entire mower shell of 7 guage steel, but Scag also welds on two more layers of 10 ga, steel in the top plate , so that the spindles are bolted onto a reinforced mower top that is 1/2 inch thick.

Scags mower construction is fabricated and their deck is 5.5 in deep-everywhere , Deere's is a stamped deck, and uses a wind tunnel design to get the grass out.
I won't get into that controversy about the merits of these two designs, but I can say that other companies [ like MTD Pro, Lesco. Toro, Cub Cadet, and even Kubota] that have used stamped decks before, are now all using Fab. design on most all their mower decks.

The Scag mower deck has a DRIVE SHAFT with a universal joint at each end to power the mower deck. This is how it's done on large utility tractors and most of the larger commercial mowing machines. The Deere uses a belt to drive their mower deck [ which is OK to do] , but the problem is that they run this belt over a pair of rear idlers , which twists the belt 180 deg. and then it goes to a pulley on a horizontal crank engine. This twisting of a PTO belt has been done on many garden tractors, and was even the way it was done on the old Cub Low Boy tractors of 50 years ago. It has always been a poor way to drive a mower, and the extra friction and rolling/twisting resistance will use a couple of horse power, and will certainly shorten the life of this expensive belt. The only advantage of the twisted belt type of system, is that it is cheap to make and saves Deere a lot of money.

If you open the rear service panel on the Scag Tiger, the hydro drive belt is right there and so is the PTO drive belt. The pair could easily be changed in less than 5 minutes. You will also see the 275 ft/lb PTO clutch there and so easy to service. You may also notice the PAIR of 16cc Hydro Gear pumps that propell the hydro motors. Scag uses larger 16 cc pumps because they will last much longer than the 10 cc pumps that most others have.
Now look at the Deere. See the belt down in front of the engine ? This drives their SINGLE pump , that internally divides into a pair of 10 cc pumps. This system is super criticle. If anything happens internally to this pump, it is likely to fill the entire drive system with schrapnel ! Again this systems only advantage for Deere is that it is cheaper to build !

Did you notice that the Scag Tiger has no fuel tanks outboard and above the tires ? Their single 10 gal. tank is low in the center of the frame. This greatly lowers their center of gravity. It also keeps the unit better balanced. When a twin tank machine has an empty on the left, and a full tank on the right side, they can really get weird on a hillside, but the Scag with its CENTER located tank always stays in balance, no matter what the fuel level is. Finally the inboard tank on the Scag would be virtually impossible to damage or split open in an accident. Their system is very safe for the driver. The large , high ,outboard plastic fuel tanks on the Deere are much easier to slam into an object as you make a tight zero turn - then you can have a bit of a problem !!!

If you will go back, and closely examine every aspect of each of these machines [it really helps to have them side by side] and it's even better if you can demo ride them and mow with them side by side, then after doing this - can you tell me one single thing about the Deere that you believe to be as well built, or as well engineered as the Scag Tiger ?