When they list all those different ones.... I have been told by one rep at a company, they cannot tell you how much of each.

All the other chelates are very large in size to get appreciable magnesium. So the tablet would be huge or the directions would say take 2 or 3 to get that dose.

Magnesium oxide is concentrated and has alot of chemical magnesium in it. 40%... the highest I think. But it is so tightly bound, it doesn't cross into the blood stream. It allows for smaller tablet sizes etc. I personally think they put those long sounding chelate names on the label to be impressive.

I do think aspartate is to be avoided, because the NMDA receptor is a pain receptor that is activated by aspartate. (this is why some people get headaches and other side effects from
Nutrasweet which is 1/2 aspartic acid.

Magnesium glycinate, and Slow Mag, are about the best and most commonly used. WalMart has 60 SlowMag for $9.99 and at 2 a day that's a month's supply. They also have a generic behind the counter. I get mine at Costco, behind the pharmacy at generic price too.. about $5.00 for 60. Generic is Mag64 or MagDelay (both have the Mag64 inside but just different distributors).

3oz of unsalted almonds have 270 mg... sometimes I just do that. Navy and black beans, also are high. Green veggies have chlorophyll and hence magnesium (magnesium is in the chlorophyll molecule).

The Chantix is a dopamine agonist... so when you stopped it, you could have stressed the muscles. Dopamine agonists are used for restless legs and PD. One doctor offered me Sinemet for my cramps, (the dopamine agonists weren't on the market then), but I passed on that. I went the magnesium route.
Suddenly stopping the Chantix would have been stressful metabolically for you, even if you didn't notice it.