This a common problem and the best solution is to get a critique from your ideal prospects--a focus group, if you will.
Here's why: If you ask your fellow marketers, the can be helpful but their feedback will be mostly subjective. I like this, I don't like that. This is color is too bright and this headline is boring.
What you really want is to determine if they will buy. So do whatever it takes to find a dozen or so people who are your ideal buyers and then ask for feedback. Leave out, order details or URL.
The true test, you will be looking out for is this. At least a few of them should ask you: where can we find this thing
I learned this from Dan Kennedy, one of the greatest copywriters of our time. Whenever he did a direct response piece, he'd buy a round of drinks for a dozen or so of the campaigns ideal buyers and look out for this sign. He never lost money, if a few of them asked this crucial question.
Whenever he want against this rule and thought he was a genius, the campaign flopped.
Many times I've been told a landing page I designed was ugly and that nobody would read that much copy. But the campaign made lots of mulah! And other times I've seen "expert" marketers promote a page that looked "pretty" and won designed awards. But it lost money.
The only opinion that matters is that of your prospective buyer. Period.