Ancient tube preamps vs. new gear

[OldCopper]

I've gotten it into my head to get a mic preamp to interface with my DAW instead of going through my Mackie 1604. I'm using a Rode NT-2 mic.

I started looking at Pro-MPAs and DBX 386s which are way cool and in my price range. But in tripping around the web I've found old Ampex 350 units stripped down to their preamp, rack mount sections. I was looking at an early, all tube (no PCB) model. I have no way of hearing one of these critters. Assuming the tubes are good and the caps are up dated are there considerations in using one of these? Is it crazy to spend as much on one of these units as I would for a dual channel preamp of recent vintage? Yeah I know I'd have to get a phantom power unit, too.

I'd appreciate some advice.

thanks,

Mark