new tyres needed pirelli or michellin

[maddog04]

ok, need a new pair and looking at Michelin pilot 4 or Pirelli corsa's

mainly motorway work unless I'm doing the RoSPA course which is a mix, ride all year in all weathers and looking for long life
currently on Avon ST which have been good but hearing good reports on the above

any advice warmly accepted
cheers