Chosing H8 halogen bulbs...whats the diff?

Is there any difference between these 3 H8 bulbs from these 3 vendors?...besides the price difference. Does anyone know from experience which one is brighter than the other?
umnitza - Predator Xenix HyperMatch 4200K- $24.98 + $10.55 (shipping) = $35.53
DDM - Halogen H8 bulbs 4000K - $14.95 + $13.08 (shipping) = $28.03
E92-Lighting - H8 SUPER WHITE 43550K - $22.99 + $7.99 (shipping) = $30.98

Without having ever seen or used these bulbs, I can tell you that they are blue tinted halogen bulbs. The primary difference is slight differences in "whiteness" of the beam. Halogen bulbs emit a slightly yellow (lower K value) tinted beam. Most buy these tinted bulbs to get "xenon-like" performance without knowing any better. Yes, the beams are whiter. However, the light output is significantly lower due to the blue tint, which absorbs the yellow light to give a whiter beam at the expense of light output. Unless you boost the wattage (creating problems with wiring, DOT illegality, etc.), your lighting performance degrades. Since you are asking about H8s (and not H7s), I presume these are intended for your foglamps. This is a cheap and easy approach to match up your foglamps to your xenon beams. However, your poor OEM foglamp performance gets really poor using these bulbs. Bottom line, this is a cosmetic change (nothing wrong there). Just don't expect any lighting performance improvement. Been there, done that.

See http://www.danielsternlighting.com/ for everything you ever wanted to know about auto lighting.

Originally Posted by ill_kuma

Does anyone know from experience which one is brighter than the other?

As a slightly OT aside ... I don't profess to understand bulb tradeoffs, but, bear in mind that "brighter", in and of itself, is not always the only consideration you may be concerned with ... (the links may help answer your question though).