Benchmark DAC1 vs CAL Sigma

I have an old CAL Sigma I in my system. I generally like the sound, it's musical & dynamic, however there's a bit of shrillness in the top end that I find off putting. I'm wondering how different a modern upsampling DAC such as the Benchmark DAC1 or a PS Audio Digital Link III would sound in my system? I'm a bit of a noob with external DACs so any input would be greatly appreciated.