Dupont did list a 28 gauge load with 700X at one time. If I recall it was only with the 11/16 oz shot charge and probably with fiber wads. I had an old fella now deceased (not from his reloads)that used 700x in his 28 ga. I mentioned to him that that was to fast a powder for the 28 and his remark was that it was listed. Yes it was listed with 11/16 oz of shot,not 3/4 like he was using. He shot that load a lot without any problems in a 20 ga Winchester 101 with 28ga tubes. Dupont did not list it in later manuals,I wonder why? I have used green dot with 3/4 oz and really liked the clean burn and low charge weights. I had some problems with older Unique and gave Alliant a call about it. I was told that Unique was the better choice over green dot due to consistency and lower pressures in warm weather in the 28ga. I solved my problem with Unique and find it to be a great powder in the 28. SR7625 was also a very clean low charge weight powder but got expensive and is now discontinued anyway. A friend of mine had a bad shoulder and was finding his 28's recoil a bit much for him. At that time I was loading SR4756 since I had a lot of it. I noticed that the recoil was very soft with this load and let him try some,he switched to that powder real fast even though it burns dirty with 3/4 oz loads leaving a lot of flakes in the tubes. Not to bad in a double but I wouldn't want to use it in a auto or pump. Now I think 20/28 is my go to powder if I am just buying for that purpose. You can't beat it.
