Note the caveat, though.  Tannin's vague translucence means this shade is subject to variables, according to the nature of the light, thickness of application and especially your own underlying colours.  If you're lucky, you'll get that dreamy sanguine warmth infused with a suggestion of syrupy tomato and rose-jam.  But for some, Tannin will show a more generic face, rendering as a straight-up, albeit high quality, dark raspberry, which is nice enough, even if the magic does miss you.

On my dark, bare lips, I get a warmer, murkier, more painterly look than I do when applying over something like UD lip primer. 

Tannin's x factor lies in both its gorgeous, almost fevered depth of colour and luscious texture.  It's weird how rarely those two things go together, even in this day and age.  Online images don't really do this shade justice because it's one of those reds that looks somewhat pedestrian to the camera sensor- the human eye is far more sensitive to the nuances that make it great, so it's easier to describe than to accurately depict.  Tannin is a deep, slightly debauched, burnt-jam red with a puff of smoke blown over it, just 'off-clean' if you know what I mean.  Sauce, coulis and reduction are the words that come to mind; on the right mouth, it is luscious and arresting, overwrought and juicy as only this Bite formula can be.  

You might have gathered that I personally adore Tannin almost unreasonably but I'm trying hard not to let that bias my assessment.  So- downsides? Given that they are devoid of a lot of the nastier preservative crud etc. found in mainstream products, Bite sticks can be a wee bit susceptible to heat and humidity fluctuations, both in the tube and on the lip.  Deep in the arsecrack of a disgustingly hot summer, I noticed that greasiness can surface under trying conditions. Thus Tannin can be a tad mobile on the lip when worn heavily and can also skip the centre, which is annoying if your lips are somewhat poofey and turned out like mine.  I use a brush when this is happening.  It might possibly bleed on someone especially prone to that issue, but I have old-lady lines and don't experience any problems.  

Finish-wise, there is a plumping, satiny lustre, heightening to medium glossiness depending one how much you pile on.  It is very comfortable to wear and deliciously hydrating.  There is a hint of sweet flavour and a fruity scent; they aren't grotesquely synthetic and don't bother me.