Is "more informed decisions" or "better informed decisions" the more correct form?

I'm writing some copy for a marketing campaign that promotes the use of a software testing tool by demonstrating how the results of the tool provide you with a greater wealth of information on which to make business decisions.

In relation to this, I'm using the term "informed decisions" and my initial wording included the phrase "help you make more informed decisions".

The phrase "more informed decisions" is one that is common to me and from a Google search appears to be common in the context in which I am using it, that is to denote that with additional evidence a decision can be more informed than without.

I considered whether this phrase runs the risk of being misinterpreted or being confusing due to a slight ambiguity.

The phrase "more informed decisions" could be interpreted as meaning decisions that are more greatly informed, or it could be interpreted as a greater number of informed decisions (e.g. here is one informed decision, here are more informed decisions).

I then considered the phrase "better informed decisions". I feel this has the same intended meaning but removes the above ambiguity. It could refer to decisions that are better informed or it could refer to informed decisions that are better. Both are on subject and would be fine to me.

A quick Google search suggested that the phrase "more informed decisions" is significantly more commonly used than "better informed decisions".

I have a feeling that "better informed" is more grammatically-correct than "more informed" although I have no formal basis for this.

Out of the phases "more informed decisions" and "better informed decisions", is there a more correct form?

Use "better-informed." In this context, "better" modifies "informed," so those two words should be hyphenated.

Please see http://www.merriam-webster.com/dictionary/well-informed

They are both equally correct and equally ambiguous. Better informed decisions could be read either as decisions that are better informed or as better (informed) decisions. It is just as ambiguous as more informed decisions and for the same reason. In each case, the adverb (better or more) could apply to either informed or decisions.

So, since both versions are ambiguous, go for the most common one. Personally, for example, I would immediately understand more informed decisions as decisions that are more informed while I may well parse better informed decisions as decisions that are equally informed but better.