Well, they both seem extremely entry level, which if you're new to bikes isn't necessarily a bad thing. However, they're drastically different sizes and they're made for completely different things. The white one is a track bike. Not really made for street riding. The black one is a street bike, not really made for track riding. Figuring out how you're gonna use the bike, and what size you need are vital.

Also, I couldn't help but notice that on your first post, you picked two pretty much generic bikes from the same retailer to link to, even though there are thousands of better bikes on eBay. If you're a shill, knock it off. If not, welcome.

Oh, and Kilo TT's are pretty ok I hear.