Solgar is good, and Source Naturals too.
As regards Solgar I used the 1000mcg a long time ago and was not very happy because the nuggets (as they call them) dissolve super fast.
The 5000mcg however don't have this problem, they last quite a bit and are effective.
Country life have very good ingredients and little sugar but they dissolve almost instantaneously. If you put them between cheeck and gum they last almost an hour but I don't find them very effective, this way. I used an entire bottle in August and slowly noticed several symptoms returning, related to B12. When I switched back to Source Naturals I immediately felt the effect and recovered in about one week.
cheers