Touchbar. Definitely Touchbar.
I become more preferential to the touchbar with time due to both its performance advantages and the touchbar's increasing maturity. With that said, I previously owned a nTB and liked it. However, it was not my primary computer as it was my travel machine, and the nTB would not have met my needs for primary usage. IMO, anyone using a Mac should have an App called BetterTouchTool - it literally is transformative to productivity, and with its ability to customize the touchbar, you will likely see the TB in an entirely different light; again, in my personal opinion.
If you plan to use external displays, and especially if you think you may want to use it with a 4k display or television, I think the touchbar is justifiable on this point alone - it will run quieter and smoother, and when performing resource-intensive activities while simultaneously driving a 4k display (or two 4k displays, or multiple 2.5k/1080p displays), you're likely going to get more usable processing power and less fan noise. Further, you can run dual displays on the TB without having to invest in either a pricy dock, a pricy monitor with USB-C charging, (or relying on a less expensive hub that utilizes passthrough charging with questionable longevity, and lacks any sort of certification regarding its safety.)
I'm not a medical student but I am a researcher, and I assume medical students have to do a crap ton of research. IMO, multiple monitors increase productivity. Further, there is evidence supporting this based on the outcome of several mixed-methods studies. If you do not already use one or more external displays in combination with your existing computer, chances are you will, and chances are once you do you will never be able to go back. Currently, across my three displays with my 15-inch MBP setup, I've got one monitor running a Windows VM with Tableau, another monitor running Excel on the host OS, and the third monitor displaying a split screen between a tab of about 60 PDFs of various research reports and a Word document of a final analysis that I am composing. Literally, it would be insane how much time I would waste having to switch between these individual Apps with a single display! So this is why I am stressing this issue. If this doesn't apply to you, I apologize.
If you plan to use more than one wired device at once with any regularity, this also IMO justifies the touchbar.