It won't be two years. Once I started watching Breaking Bad, which was all via DVD at the time, I got through them quickly. I only started watching it after about 3 or 4 series so had to wait for some to actually get released but flew through most of it.
Saul, I started early on in its life but for some reason I couldn't tell you now, didn't get past the first few episodes. Went back to it last year and paced myself a bit but still got through it all fairly quickly.
Personally, I'd still start with Breaking Bad because, imo, it's so astonishingly good. I just don't think it will have the same impact if you have seen Saul first.
As far a drama series go I'd expect Breaking Bad and The Sopranos to be 1 & 2 on this list: that's how good both series are in my view. No point now pretending that they were not top of my list or that, metaphorically speaking, I had to toss a coin to decide between them. I won't go as far as saying which won until one of them appears in the list.