Well it is a case of buying the mower you would rather pay for than the one that is right for the grass you are cutting.
Not all mowers will cut every kind of grass.
That is why there are a variety of deck styles and blade configurations.
A good mower shop will ask you what grass you have growing, what the yard looks like, how often you cut the grass, how long you like the grass cut and then point you to a mower that is right for you.
However most people just shop on price then get dissapointed when they do not get the cut quality that they thought they should.
Some decks are really deep to provide a strong draught in order to cut fine grass , some are shallow .
Most decks will take a variety of blades again to suit a particular customers grass.
People with lot of obstructions need a deck with extra overlap so you don't mowhawk when you turn.
Some grass suck as couch or winter grass is best cut with a drum because it is too fine for the slashing motion of a rotary.
Toro actually went to the effort on printing a grass cutting manual called the "Quality of Cut Guide" to explain come of the theories behind grass cutting to allow customers to select the deck that best suits their grass.
Now if you have a problem then tell the forum what it is and perhaps some of the professionals can steer you in the right direction.
And by the way, if you look at my profile you will note my mowers all date from the 60's and none of them are green.