I'm now using the Epson T2100 with refill since about 2 months and can report some peculiarities I didn't know when I got the printer. Both the Epson T2100 and the Canon TC-20 are part of a product family of entry level large format printers of the resp. company. As mentioned already the Epson T2100 is offered at about 800€, the same as the TC-20, the TC-20 is a Megatank printer, the T2100 runs on cartidges. An Ecotank version of the T3100 is offered as well at a much higher price - at about 2200€ which let you quickly look for refill options. I'm not familiar and have not tested the Canon TM-240 , a similar printer running on cartidges as well, this model with 5 pigment inks incl 2 blacks, the T2100 and the TC-20 both with 4 pigment inks. The Canon printer uses the pigment black ink as well for printing on glossy paper, it is a kind of universal ink for both matte and glossy papers. The Epson ET-2100 does not use the prigment with the driver setting on glossy paper which affects the effective dark point, the mix of the CMY colors is not as black as a real black ink. But since the ET-2100 runs on cartridges it is easily possible to use 2 different black inks - for matte and photo papers - and switch the cartridges as needed - and print with the matte paper setting in the driver onto glossy paper with a photo black ink - it makes a visible and measurable positive difference - and as well when you create an icc-profile.
The print quality of both models is very similar and good, the T2100 runs with 4 pl and the TC-20 with 5pl droplet size, monochrome areas are smooth, and some noise is only visible at very close distance. There are rather slight differences at close viewing distance but that would not be a reason to prefer one model over the other. All these printers are not marketed as photo printers, not at all when you browse through the marketing brochures, these printers do not print borderless. A limit is specified for the paper thickness - 0.27 mm for both printers, this does exclude any thicker fine art like and other heavier papers - a 250 gr highgloss photo paper works without problems.
The question about banner printing and the max. paper lenght comes up now and then - the Canon TC-20 prints banners up to 4 m, the Epson T2100 let you set the custom length to 91 meters (!)- that's about 2 rolls of paper. I don't know which graphics program can handle that and whether Windows could handle such a large spool file.
And there is another limit - the paper roll diameter cannot exceed 11 cm which limits the paper roll size and excludes paper on a 3" core. Or you unroll some of it onto a 2nd roll.
The inks for the TC-20 come in 70 ml bottles and are keyed so that you cannot fill them up in the wrong color tank, very easy and reliable. the TC-20 has ink sensors in the tanks, and the printer might send you an email whenever there is a problem with the inks running empty or the paper or else. That's part of the overall functional setup.
The Epson T2100, and the other similar models like the T3100 - T3170 in some countries - use cartridges T40Cx with 25 ml content for the CMY colors and 50 ml for black, or the T40Dx cartidges contain 50 ml for CMY and 80 ml for black. And this is starting to create problems. All cartidges have a chip counting down the remaining content, but there is no resetter on the market at Aliexpress nor ARC chips are available. You need one-time chips which are sold at pretty igh prices - about 10 - 12 € per chip per color.
https://de.aliexpress.com/item/1005007703211841.html?spm=a2g0o.buyer-tracking.appTrackingRecommend.1.296e7df9tv5Ywj&gps-id=appTrackingRecommend&scm=1007.30509.402598.0&scm_id=1007.30509.402598.0&scm-url=1007.30509.402598.0&pvid=d1955345-286f-4a8a-bd50-0af662d649bf&_t=gps-id:appTrackingRecommend,scm-url:1007.30509.402598.0,pvid:d1955345-286f-4a8a-bd50-0af662d649bf,tpp_buckets:668#2846#8114#1999&pdp_npi=4@dis!EUR!15.39!15.39!!!16.29!16.29!@211b80c217293275595234259e8f61!12000041915502520!rec!DE!160539225!XZ
This is eating up all benefits of refilling this printer. You can get refill cartidges labelled as T40Dx to which you attach the chips but these cartridges only take 25 ml, but the chip counts down 50 ml. This requires you to refill the carts when the chip has counted down less than 50% so you need to monitor carfully the actual and the chip ink levels. You can buy compatible cartidges which are priced at about the price of that chip + an empty refill cart.
I tried to refill various carts - refill works with the original cartridges and replacing the chips, I had problems with the alternate carts - the ink outlet does not seem to be closed by the spring loaded valve as most Epson carts have, and I had some ink spill with such 3rd party carts. I'm refill doing now only with the OEM Epson carts. And before I forget it - both printers support printing onto single sheets - A4 or larger up to A3 - the paper bin takes about 20 - 30 sheets of plain paper or less of thicker photo papers. You just select the paper source via the driver. It just works fine. If you print photos onto glossy paper you might compare the gamut to other photo printers - the gamut of these 4 colors printers is smaller than the gamut of the 8 or 10 ink printers, but as long as you don't have a print available for comparison from such printer you don't get the feeeling that something is wrong with the printouts on the T2100 or TC-20. Keith Cooper has tested the TC-20 recently with an overall positive verdict
https://www.northlight-images.co.uk/canon-tc-20m-printer-review/
If you want to know more about these printers - just get the user manual - it's just about 500 pages for the T2100 + 200 pages for the network setup and operation - and about 1000 pages for the TC-20 incl. the network setup and operation. Everything, every option, every step is described in great detail.