DAC Dilemma

I will (probably foolishly) put my decision before you all and see if I get any informed opinions, or if I just get scoffed at. I have been at this hobby many years, but must admit to not having the sophistication that many of you do. To those of you that are DAC experts. I have read, and it is my understanding that DAC technology has progressed to the point that 1) new "entry level" DAC’s blow away earlier generation DACs that originally cost much more, and 2) the difference between most current DACs as far as sound quality is pretty subtle. I have an Aurender N100H (which is going to stay) with a PS Audio DirectStream DAC (Not the $6K version. The $3K version with no bridge) feeding into an Audio Research SP16 tubed preamp into a high end solid state amp. Should I 1) just keep what I have (yes, it sounds good, but it could always be better) 2) replace the PS Audio with an Audio Research DAC7 that is about 11 years old but very well reviewed in it’s day, or 3) sell the PS Audio and the Audio Research SP16 and replace both with a Benchmark DAC3 HGC. The Benchmark would give me a current Class A DAC along with multiple inputs for digital, and two inputs for both of my turntables, thus eliminating the need for a separate preamp. But, would the Benchmark SOUND better than either the PS Audio DAC or the DAC7? I am very much aware that the DAC's mentioned above address the actual digital to analogue conversion in very different ways which is precisely why I'm asking which one you think gives the best (natural, uncolored, transparent) sound. Opinions please.