Uptone EtherRegen or Gigafoil v4???

I've read a great deal about both the EtherRegen and the Gigafoil v4.  Has anyone tried both of these units to compare?  
I've gone to a total streaming system now, and I'm wondering how it can get better than what I currently have.  What does something like these units do to enhance the sound?  Is it worth the $650 for either of these units?

Also consider the Network Acoustics ENO Ethernet Filters.  They seem to be the recent "darlings".
I am a ENO user....biggest advantage with ENO is passive filtration of incoming noise on Ethernet. Read up on ENO here before invest in any other solution,

I’ve had the EtherRegen, Gigafoil and ENO in my system. In the end I kept the Gigafoil and ENO. I have the ENO right before my streamer. I don’t think the Gigafoil is better than the EtherRegen but the ER gave me dropout issues and required rebooting frequently. -Alex
Whatever you choose use fiber optic cable, it is a big upgrade over ethernet.
P.S. I use the EtherRegen. Never tried the other one mentioned. 

You can use ethernet now with the advent of Network Acoustics ENO ethernet filter and cables. Amazing sound without a bunch of boxes.
I'm an Eno Ag user as well, it replaced an etherRegen. In the end I found the Eno Ag to sound better in my system and since it's a passive device I was able to eliminate an LPS. 

The Gigafoil works much like using two FMCs with a short run of fiber between them. 
I haven’t used the ER, but I can definitely vouch for the Gigafoil in my system. When you can get an audible improvement for $500, I’d say that is a good deal.  Does it “blow me away” or “sound like a totally new system?” Of course not. But it is an audible improvement.  I have generic CAT6 from the wall to the Gigafoil, then generic CAT7 from the Gigafoil to my MSB Discrete DAC.  I am thinking of putting in a ENO Ethernet cable from the Gigafoil to the DAC, but curious as to whether there would really be an audible difference there . . .?

I suggest installing Supra Cat 8 LAN cables between wall to Gigafoil and then Gigafoil to MSB DAC. You are very likely to hear audible improvements over generic CAT6 due to superior shielding and noise reduction. 

Agree with lalitk that Supra is big value for money on Ethernet cable front. I use them all over 

I use a Gigafoil. Not essential but good easy streaming tweak. More of an improvement with my old Naim setup for whatever reason than with my current totaldac setup 
No dropout issues 

Curious about ENO. As noted above, possible to pair with Gigafoil
On another thread, folks are raving about the ViaBlue cable and the ENO cable.  I wonder if replacing the short CAT7 run from the Gigafoil to the MSB Discrete DAC will actually make an audible difference.  The ViaBlue is about $100 and the ENO cable is $700.  Moreover, even if there is an audible difference, I wonder just how much of a difference there would/could be to justify forking over $700 for an Ethernet cable at the very end of the system?  Did you find that using a better than generic Ethernet cable actually made a difference in that short run?

I had the Eno and Gigafoil on hand at the same time and auditioned both extensively..In my system it was no contest, the Gigafoil made a PROFOUND difference as opposed to the ENO's VERY subtle difference. I sent the ENO back and have the GF, still very happy with it. I have it right before my Antipodes Server.