I had ECB + 0.50 % tracker with Danske Bank. which moved to Pepper some years back, took it out from around 2005/6, but as with all of these, you had to have a low LTV.
At the time i took it out, the 0.50 % rate was subject to an LTV of 50 %, we just scrope over that line !
Needless to say, it was my 5th, and final bank with our mortgage.
I don’t remember anyone else offering 0.50 % at the time, i certainly shopped around at the time, but situation could have changed after i took it out.