The Cub Cadet LT1045 and the newer LTX1045 are extremely popular models amongst those with .5 to 2 acre yards. With MSRPs of $1699 and $1899, they are also fairly affordable. The LT 1045 was first produced in 2006.
Both tractors feature a 20hp Kohler Courage single cylinder engine and 46" Quickattach decks. Both have a curb weight of just over 500 pounds and feature hydrostatic transmissions.
These tractors are normally found in Lowe's and Home Depot, so they are a bit more consumer grade than some of the models found at higher end garden shops. The advantage here is that parts are plentiful and reasonably priced. Most maintenance and repairs are easy for a DIYer to complete.