Iain, I have no problem with your style of mini reviews because it sets out with one objective in mind - that is, to give us an idea of your initial impressions of the product in question. Like you said, you state as much in your title and that is all it is meant to be; a taster, if you will. Besides, anything you have to say on a product is worth reading, mini or otherwise. I put more weight in your opinion than I do many others, but that is just me.
What I do have a problem with is people who write a review, with the
intention of it being a full-blown review (and not just a taster, with more to come). But all they end up writing is, "this is fab, buy it now! 11/10". What's the point of that?
Frankly, you're an established member of this forum with a good reputation, so you can get away with mini reviews. Joe Bloggs is none of these things and so should be making attempts to gain some sort of positive reputation by writing a review that is actually worth reading. Put it this way - if Iain (or Paul, or Craig, or Mandrake, or Lomster, or Dave... the list goes on) writes a one-sentence mini review that says "buy this, it's great", I am more likely to believe them than if some "normal" member of the forum says, "buy this, it's great".
These posts are going to make me sound like an Iain-loving review snob, but that is not so. (I hate the git

). I just think that us relative unknowns should put a bit more effort into writing reviews.