I get my Tomcots lately from Van Well, who, unfortunately, graft cots on peach seedling. This has led to issues with borers, especially because I don’t really have my eyes out for borers with cots.
What will work for you is not possible to tell, but Hargrand has tended to be the longest lived cot for me of all the varieties I grow. Orangered showed great signs in terms of maintaining high vigor on my property for 5 years but this seasons events seemed to have knocked it for a loop and I’ve had it die elsewhere at less than encouraging percentage. Early Blush has also turned out to be a bust at many “better” sites than mine but on my property is going strong after losing vigor and being cut back 2 years ago. It looks ready to bear a good crop next season.
The thing is that cots act weirdly at my site- usually not getting full cambium kill but instead maybe cam injury that dooms the trees to inadequate vigor to crop well. On other sites they tend to be live vigorously or die.
I haven’t used Alfred enough to evaluate it well. It does great growing against my east and south wall and even this season I got a few cots from it- the only ones I saw anywhere not in a grocery store. I put a Tomcot on the south side and it is looking very promising after 2 years of growth there.
I’ve never gotten cots on citation- they tend to be on Manchurian.