Who has a McIntosh C70 anniversary preamp? Thoughts?

C 2700 or C 2600 if you want tubes.
C 49 or C 53 if you want solid state. 

+1

i don’t know the px of the mac preamps that you’re looking at but the Luxman C-900u preamp has tone controls and will be something you’ll own a very long time. they can be had in the 8-9k range if you’re patient(list 15k). i believe and as do many others that you will find it incomparable.

I wonder how C900U compares to more high end tube pres like  ARC Ref 6, ref6SE, VAC renaissance MK V

I've had the C70 for about six months now.  Upgraded the tubes to Gold Lion.  I'm running it with a Benchmark AHB2 amp and DAC3L.  I've had many Mac preamps over the years and all have been very good in their own ways.  The C70 is perfect, the culmination of Mac's pursuit of excellence.  You will not be sorry if this is your choice.

I have the C2700. It’s fantastic. I use the built in DAC module and have changed the stock tubes to NOS Mullards and Telefunken. I cannot imagine any reason to ever replace it.