i've dive with scuba junkie last june after getting my OW licence.. really recommended.. their staff was professional and u will be surprised to see only a few local people dive with them, however you will find mostly foreigner will dive with them..

about cost, i think it is quite reasonable.. i stay 2 nite @ semporna and 2 nite @ mabul (their mabul resort very nice..) with 2 day snorkeling, 1 day dive @ pulau sibuan and 1 day dive @ sipadan cost me only rm1300 all in.. including transfer from tawau and boat transfer to mabul..