Stock price when the opinion was issued
Corporate debt is not assessable to most retail investors. How can I invest? There are others, but this is as good as any. It is hard to get good corporate bonds, and an ETF is a good way to play it. If you are going to be in the bond market, this is where you should be. The yields are a little better. Bear in mind that corporates are not going to be immune to higher interest rates and the impact it is going to have.
If interest rates goes back, then you can get really hurt. If you want long-term, you can have some short duration bonds. ZST is a short term bond. He wouldn't buy it right now.