I will stick to R2R. Compared GG1 to Lyra atlas through Allnic 7000 and Ypsilon phono (the latter with a Lyra SUT) at dctom through the Ypsilon preamp two weekends ago. Both of us were pretty happy with his R2R GG. Then at Montesquieu with the Miyajima madake and the Allnic 7000 through the top audiopax preamp this Sunday. I returned delighted.
And based on Lampi factory trip, the R2R was so much superior to chip. Haven't compared to engine 53 yet as there was no engine 53 then but I would suggest that anyone who is looking to change should listen for R2R vs non R2R, don't assume one is better regardless of what you read on forums. There is a clear difference with R2R. If you are unable to demo both, then shift only if you are not happy with whatever you currently have.
Also, the Lampi dacs I have consistently liked (Dctom's, Bill's, what Jazzhead is now preferring immensely to his trinity, 75k Stahltek transport plus dac, aqua formula, neodio origine, and TAD are all R2R).