 However, he is now best known for the popular "Gift Grub" segments which have featured on the Ian Dempsey Breakfast Show on Today FM since May 1999 which Rosenstock created alongside Paul McLoone, a radio presenter with Today FM and also frontman of the Northern Irish pop-punk/new-wave band, The Undertones which occurred in 1999 and when McLoone served as a producer for the Ian Dempsey Breakfast Show.Gift Grub is a series of comic sketches, impersonations and parodies that have featured Rosenstock assuming the personae of Bertie Ahern, Ronan Keating, Colin Farrell and Roy Keane amongst many others; he also provides the manic voice of Right Price Tiles radio spokesperson "Daft Dave".Rosenstock performed an impersonation of José Mourinho in a parody of a song from the musical "Joseph and the Amazing Technicolor Dreamcoat".