I've been playing with stiga blades for over 50 years and are good. But ready made bats are usually for beginners. Once you have been playing for a while, you develop a style, attack, defensive or all round. Rubbers vary so much and usually you don't have the same on both sides.
Sponge thicknesses vary from none through to about 2.2 mm. The greater the thickness, the greater the speed, but control is less.
I buy the rubber sheets separately and usually Yasaka or Tibar.
Are you a casual or a league player .
Good websites are bribar or table tennis direct.