quickfire pro (SGK-4020-GKCM1)
https://www.youtube.com/watch?v=-Wn5Rq-ouiU
thermaltake poseidon (KB-POI-BRBLUS-01)
https://www.youtube.com/watch?v=nF3CQDM6w3g
Personally, it's going to come down to aesthetic. They're both low-priced Cherry MX Brown backlit 104-key NKRO wired mechanical keyboards. I'm not savvy enough to be able to tell if their build quality is any better than the other, but they look similar to me.
Quickfire pro has option of being partially backlit. If you want to see what that means, go 2/3 through the youtube video I linked. You'll notice about half the keys are lit up. You can also choose to have all of them lit up. It uses two separate keys for LEDs for: toggling brigthness, and on/off.
Poseidon is fully backlit, or no backlight. This is controlled by the same key. This difference is negligible.
So, there you go! If you are just looking for a cheap mechanical keyboard, ncix has this for $70 ending today:
http://us.ncix.com/products/?usaffiliateid=1000031504&sku=87112&vpn=ROC-12-601-BK&manufacture=ROCCAT&promoid=1084
I prefer the Poseidon just because I prefer the blue LED color and type of font printed on the keys themselves. I also like how it looks more discreet (rectangular... simple and not loud) - which is probably due to the LEDs and font differences.