First off, I need to point out that I live on the east side of Hawaii Island in a zone that gets about 150 inches of rain a year. This kind of humid environment can be rough on any kind of mechanical or electrical device, plus, it grows grass faster than the Dickens, so my review represents some of the harshest conditions available for a lawn tractor.
My household has been using the Toro LX460 lawn tractor for just under three years now. Overall, we have been pleased with this model, especially considering that none of us had prior experience with using or maintaining a lawn tractor. We mow our lawns roughly once a month, and it takes about an hour at a stretch (we have a LOT of lawn).
I would consider the Toro LX460 an upper-end home model. Like most lawn tractors in its class, it is stable on hillocks but may tend to idle and can be a bit tipsy when traveling over uneven ground, such as tree roots buried in the grass. So it is very important to go slowly on this Toro, or simply to use a standard push mower, wherever you encounter such difficult conditions with your landscape.
The OEM battery lasted about two years in our environment. I understand that this is pretty typical. I replaced ours a year ago for about 50 bucks from the local battery and propane dealer, who told me that, provided that we replace the distilled water in its capped reservoirs yearly, the replacement battery should last about five years.
Also not to be overlooked, the seat is solidly constructed and makes for a comfortable ride. There's even a spot there for your beverage.
All that said, this is a real powerhouse of a tractor. I have been very impressed with its control over lawn-cutting height, and the variability of its speed. The Toro LX460 offers a lot of power and control for the money (about $2,500 in Hawaii via Home Depot). If you wanted something even gutsier and more reliable, I'd look at a John Deere in the $3,700 range (light industrial, and a special drop-ship order item here in Hawaii), which some friends of ours have been extremely pleased with ("You can grind up rocks with this," they say. For our needs, however, we feel we have made the right purchase.
Sounds like you are using a multching blade with your bag system. Multching blades are used to finely chop the grass and put back down into the lawn. They are shaped differently and do not have the lift that a normal blade has. A normal blade has more of a fan type shape to lift the grass up the tube. Either remover the chute and bag and multch or change your blades to correct the problem.
I do to fix? Would appreciate an answer ASAP.