Both products are nice plastic ultra-microfibre
“Ultra Suede” is polyester, whilst “Ultra Leather” is polyurethane
They can both be attractive and durable; and comfortable upon which to sit.
I've never "slepped" on either.
The Wyzenbeek and Martindale tests are the two methods commonly used to predict wear-ability.
The Wyzenbeek test is an abrasion test that tests the fabric's ability to withstand surface wear from rubbing. In this test, the fabric is pulled taut in a frame and rubbed in both the warp and weft (filling) directions, using a piece of #10 cotton duck fabric as the abradant. The number of cycles, or double rubs, completed before the fabric shows noticeable wear is counted and determines the abrasion rating.
15,000 Cycles Completed - General Contract Upholstery
30,000 Cycles Completed - Heavy Duty Upholstery