The big difference is that each light bar has its own transformer, which requires a 120v power feed. It's bulkier and makes it harder to hide the wires. The tape lights can be fed by one or more transformers remote from the tape and can be connected by much smaller wires. You can get covers for tapes so the tape isn't exposed.

This my LED tape on the front side and plugmold on the backsplash side. A thin paint matched panel was installed for a clean/finished look under the cabinet. The tape lights are 3500K to match my recessed lights.

I have hardwired light bars. They have built in drivers so no transformers needed. You can connect up to 20 on single power source. They have a switch to choose between 2700K, 3000K and 4000K. They are 1 inch thick. I do not have a light rail and you still can't see them unless you look under the cabinets. They come in various lengths and 3 different finishes.

https://www.amazon.com/dp/B0142EGI0U?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_2&th=1

@Clyde Kalvin, @chispa, @Seabornman, thanks so much for your reply! Just curious, did you put the under-cabinet light on a dimmer switch? Wife is saying that it's task light so no need to be on a dimmer, but I think put the under-cabinet light on a dimmer can adjust lighting for different moods and tasks (also energy saving and extended LED lifespan and potentially can reduce glare and eye strain). Thoughts? Also, did you pick one that can adjust the color temperature, and which color temperature you ended up using most frequently? Thanks so much!!

Mine are not on dimmers but it does have a switch on the light to make it less bright. Never felt the need to make it less bright. Ours are on a separate switch from the other kitchen lights. We prefer 3000K. 2700k is too yellow and 4000K is too blue.

Sorry for any confusion. For some reason when i go through the notification link in my email it comes up with my old user name vinmarks and not Ann Marks.