I agree - although if you purchase locally (i.e. walk to the comics store) you'll discover that there's really no price difference in the US between the TPBs and the individual issues.
Typically, trade paperbacks (or "trades" or TPBs) have a sturdier cover than regular issues and often can save you a couple of bucks overall, since they are a collection of issues. However, I just started on Season 8 as well and so I added up the issue dollars versus the TPB dollars and discovered there was only about a dollar difference. It may really make a difference for online ordering when it comes to shipping price, though.
Each TPB will also tell you which issues of Season 8 it has inside - usually about 5 issues collected in one TPB. Sometimes you have to look hard for the information; I believe it's on the inside front cover of these ones. And I'm sure there's someone on the board who can tell you which issue numbers are in the two TPBs that have been put out for Season 8, anyway.
p.s. with the variant cover thing, just be sure that you look for the number of the issue you need, and that should do fine. For example, take an issue 17 and a variant issue 17. They'll look totally different on the outside, but open them up and it's the exact same comic book inside. I'm caaa-razy about these Jo Chen covers, so I just stopped buying the regular covers altogether!