Benchmark DAC1

Is it possible to hook up an amplifier to this unit and use the headphone gain control as a volume control? I thought I read somewhere you could but just want to clarify. And If one was to purchase this DAC what would be a good transport? Does it even matter? And am I right to assume that for people who want a universal player but are on a limited budget ($1500) that DAC/transport is the best way to go? Thanks