I used to get B-12 jell in single-dose packs that you would squirt up your nose to be absorbed via capillaries or whatever. I noticed a boost the first few times I took it and then it stopped. I assume I just filled whatever deficit I had been carrying and it stopped being noticeable. The sublingual B-12 irritated the bottom of my tongue. Pills do me no good as I had a good 2 feet of small intestine removed where B-12 is supposed to be absorbed(around the ileum). My doc will give me an occasional injection of it, but for some reason he doesn’t seem to like doing this.
People who don’t eat much meat will definitely get a boost from B12. There is a lot of hype about B12 as of late but I believe that there is something to it. I use sublingual tablets that I got at a local health food store (not GNC). I noticed a boost from the sublinguals that was not totally subjective as a number of my times in certain sprints improved noticably.
Just as an aside, cyanocobalamine (B-12) is far too large of a molecule to be sublingually absorbed. Whatever you are getting from it benefit wise is being absorbed in the SI. If its cheaper for tablets, I’d suggest you switch to save some cash.