I was just looking at some of my site and link stats tonight.
I have an affiliate banner + context text link above-the-fold on a home page that invites visitors to download a software
Referring to your description, I would cetainly call it 'banner-in-context'.
It gets 3% to 6% clickthrough. (But no sales this month out of 2500 impressions.)
How does click-through relate to conversion here? Evidently less than one person in 150 will be a buyer from that that page. Why? I don't know for sure yet.
Other factors I think about relating to that page: there is un-targeted traffic arriving at that page; the page is informational - not what you could call 'sales copy'; maybe the vendor's sales page (that the links go to) has some problem and discourages purchasers.
There are so many variables. And 2busy is right: sample size, topic, context are some of them.
I'm speaking as a person with a site that's about a specific topic and has some affiliate links sprinkled through it.
From my perspective, if I saw 25% click-through from ANY link I would be VERY interested in that. I'd be thinking "Now there's my latest 'featured product' that I will promote."
(Of course my interest would also depend on sample-size, commission that can be earned per sale, whether the product is reputable, whether vendor's purchase page works smoothly etc.)
Re Spanish: I don't really know about that. However, I have promoted Panda computer
security software: the company is from Spain. An affiliate manager from Panda hangs out on these forums.
He was very helpful to me as a newbie affiliate - even though the problem I had wasn't his responsibility (and I have only ever made one or two sales of Panda products).
In fact, my exchange with him was one of the experiences that reminded me that this business, full of rogues and half-baked schemes as it is, can also be a civilised business where we deal with helpful, ethical people.
Anyway, good luck with your efforts. I'm just learning too.