Email Marketers/List Owners: Are these sexy figures adding up?

Hey folks,

I was just playing with some numbers and projecting my income
from a new list I am building. I was wondering if you would agree
with the numbers I was playing with and if you'd like to offer
different opinions? Here's what I was thinking...

Buy 1000 clicks at 30cents per click = $300

30% Opt in to your newsletter = 300 opt ins

25% confirm their opt in, 5% are lost = 285 CONFIRMED opt ins (now valid leads)

30% of your confirmed leads regularly open your emails = 85

10% of your regular "openers" buy your product = 8

Using an example of selling a product (affiliate or otherwise) with a $24 commission, you would theoretically make a net income of = $192

So, you'd be losing out in this typical scenario. You'd actually need to make another $108 from your subscribers to break even. That would mean...

$108 / $24 (your commissions) = 4-5 more sales needed from this list to break even.

What are your thoughts on these numbers? Do they look
fairly typical to you?

P.S

This is not a slant on email marketing, in fact quite the opposite,
as any initial promotions simply help to recoup ad costs, and there
are so many factors than can help reduce ad spend and conversions,
so please take this positively...I am trying to sensibly calculate my
initial ROI before promoting the numerous backend products for this
market.

In other words, I have no doubt I'll make money from my list, even
if I paid $1,2 or even $5 per click due to the vast amount of backend
potential.

Just wanted to see if other people think these figures are sensible ;-)