Simaudio 680D?

So, I’m hoping I can leverage some of the collective experience of the forum.  I’ve been improving all elements of my system and the DAC is next.  The problem I have is similar to what so many others have experienced - inability to properly audition a unit.  Units under consideration are:
Simaudio 680D
Auralic Vega G2.1
Bricasti M3
Holo Audio May KTE (based on reviews and some ‘gon forum dialogue)
Denafrips Terminator (per recommendation from forum participants I’ve come to really respect)
Marantz SA-10 (a SACD player w/ digital in)

Simaudio: My local SimAudio dealer will only get a unit in if “I’m ready to buy it”. By that, he means I purchase it and can return it if it doesn’t meet my expectations.  I do understand the policy because he has to purchase it from Simaudio - so he has costs up front.  He’d be able to return it to Simaudio, but yeah - it’s a hassle. He doesn’t need tire kickers. I heard the Simaudio 390 (preamp/DAC) at the dealer and thought it nice for the price. The 680D, being a dedicated DAC w/ no preamp, should be much better as it’s nearly 2x the price. It also has the MIND streaming module which would allow me, theoretically, to sell my streamer.  However, the MIND function of the 390 fell way, way short of my unit so I’m skeptical on that element.  I assume it’s better in the 680D but this is an important function that many overlook. I’d love to hear from some users on their experiences and impressions of this unit.

Bricasti: same deal, different dealer -  he’ll happily sell me one which I can return within about a week if I don’t like it.  His store is about 2 hours away.  It, too, can be used as a server/renderer but it doesn’t have a good software solution so I’d have to go back to Roon.  And, again, I’m unsure of the quality of the streaming function.

Marantz SA-10: about 2 hours away and they’ll let me take a unit from the store for home audition. I’ve purchased a good amount of gear from them in the past so I’m a trusted customer.  This is primarily a disk player (which would be nice as a I have a number of SACDs I can’t currently play).  I really prefer streaming and have a nice enough unit that streaming is as good as playing a silver disk.  I’m sure the SA-10 is a great disk player, but I’m unsure it’s competitive with the other as an outboard DAC.  At least i can try it, even if I can’t compare it to other units.

Denafrips and Holo Audio: both are R2R topologies with terrific reviews and lots of forum support.  But, there are no dealers in the U.S that I’m aware of. So auditions are impossible and I’m unsure of return policies.

Auralic Vega G2.1:  can’t find a dealer who has one. I have the Aries G2 streamer/server which I think is very good and the two together are supposed to be excellent.

So, I feel stuck.  I’ll certainly audition the Marantz but won’t be able to compare it to any of the others. So, memory will have to suffice.  

I’d welcome any input/suggestions the forum can offer.

Related gear:
Speakers: KEF Reference 3s
T+A PA 3000 HV integrated amp
Auralic Aries G2 streamer
AQ Niagara 5000 conditioner

Budget: up to $10k but lower is better, of course....