You might want to try to find "high CRI" LED lighting (something with a CRI of at least 90). Under regular LED lighting red colored objects can sometimes appear a bit dull and greyish, if that matters to you at all. It's not just red colors, earthy-colored ceramics and wood hues can also look a little sickly. Good LED lighting can make things look more colorful and vibrant than fluorescent.

If anyone is interested, contrary to my own plan I wound up installing the UC panels under the front of the cabinets instead of the back. I did this everywhere except the PT holder. There, I mounted one just behind it, not all the way to the rear. The choice for me was simple: I could see the panels in the back and not in the front. The PT holder hides the panel to an acceptable degree, and there is no noticeable inconsistency between the PT panel and the next one in front thanks to excellent diffusion. The glare/reflection I worried about is not a factor and I've got a dual wireless dimmer mounted to the wall. Very happy with the results! Thanks again to everyone for your help. Btw, I used "Independence" dimmers and "Designer" panels both by InspiredLED. Peter did a good job, quickly providing plans and suggestions and also fixing a hiccup when a piece arrived defective.

Our electrician recommended these for our new build (still under construction, so haven’t experienced personally):

Whether the thickness of the fixture matters depends on the design of the cabinets. I have IKEA cabinets with a "deco strip" attached to the bottom of the cabinet that hides the underside of the cabinet as well as the under-cabinet lights and wires. It hangs down 2-1/2" below the cabinet so it would hide a 1" or 3/8" thick light. The SlimEdge lights are available with color temperatures of 2700K and 3000K while the Enbrighten is switchable between 3000K-4000K-5000K. IMO 2700K is definitely too low (i.e., light is too yellow) for a kitchen and 3000K is on the border. Before deciding, I'd pick up one of these Commercial Electric Selectable Integrated LED Downlights ($20 at Home Depo), attach the downlight to a lamp (screw the connector into a lamp), and experiment with various color temperatures and brightnesses, shining the downlight at your countertop and other things (e.g., backsplash, food) that will be illuminated by the under-counter light you ultimately choose.