Dunhill's nightcap set me on my ass a couple of times, and I have a pretty high tolerance for nicotine. Usually after I had 2 bowls, back to back, but even one should do it for you. Depends a lot on if you like the stuff too. I found Rattray's Hal o' the wynd to be pretty strong for a virginia blend as well. It's written on the tin, which may lead to subliminal suggestion, but I think it's accurate.
If you really want to quit chewing tobacco, just start smiling at any ladies you're trying to impress right after you finish a plug. Their reactions might turn you off from the stuff! Well, if you enjoy it, do what you like, but from your post, it seems like you're trying to kick that habit. I never really saw the appeal. That, and including snuff. It just seems so messy and the people I've seen doing it... well, hocking up big gobs of black spit/phlegm/teeth/and whatever else comes up is pretty damn gross for most people to sit next to.
Of course, it does have a mild badass effect, like when someone like me says something offensive to a guy like you and your reaction is to hock that shit on to my shoes. That's an impact to be sure.
Anyway, Nightcap and Hal o' the Wynd. Those are two very different, but strong blends.