I too switched several years ago from using Tmax 100 or Tri X developed in tmax developer or Hc110 to shooting Ilford Delta 100 and developing it in Xtol. There was a big difference for printing scanned negs.
I shoot only 4x5 iso bw and scan with my Aztec 8000 DPL driven drum scanner. I've probably printed about 30 40x60 inch prints from this combination and a lot more smaller sizes over the past few years. I use Piezography K7 Carbon inks in an Epson 9890 printer, driven with QTR and custom linearization. When I compare my older prints scanned and printed the same way but with Tmax I see the grain, even with these great scans and inks. The Xtol is sharper, smoother, and with far less grain. It scans easier and it prints easier.
When you look at these Delta-Xtol prints now you see NO grain, even at this scale. It's remarkable how much different that developer made for me. I hope they keep making it because it's working perfectly. It is inexpensive, comes in dry form with a part A and part B that allows you to mix it at room temperature. Its very easy to use and mix. I have heard that using TMax 100 in this Xtol is also very similar in result. My development time with diluting the stock solution 1:1 is 13 minutes at 68 degrees F. in a tray. I buy it from B&H.
john