Grip should be optimised on pavement/tarmac as a steel shoe can be very slippy on these types of surfaces. Also they can be very hard on the shoes wearing them out prematurely.
Traditionally, British riders do more road (tarmac) work than the rest of Europe, with gradually increased distances of walk and trot on roads/tarmac. There is one school of thought that road work strengthens the musculoskeletal system. This can be quite hard on the horn and may cause bruising.
A wide web shoe will give maximum support, cover and durability, but will be very slippy on such a surface. Additional traction is recommended with either road pins or ESL road nails. A concave style shoe will give additional grip, but will not be as durable and will wear out more quickly.
If you choose to use a shoe without additional break, it is recommended that you apply either a rolled toe or a rocker toe. This will help the horse with the rolling breakover against the hard surface, prolonging the durability of the shoe