Get the Cobra. I have less then $2000 in my car and pretty much no one in my area can hang with me. Well other than the people that own Cobra and those pesky Vipers and built Vettes.
Looked at buying both cars. I ended up with a Cobra and after paying $26000 for a Cobra that had $3000 in mods and has 465rwhp. I couldn't be happier with my decision.
I have a Steeda which works great. I would have probably gone with a K&N but I bought the car used and it had a Steeda already on it. I can't complain it looks really good and seems to do the job.