Hmm I need to rectify this mistake. Sorry it took so long for me to reply. After the initial few days of no responses I stopped monitoring this thread. I was at the beach when my roommate let me know the package had arrived. I asked him to open it and that's the conclusion he gave me when I asked. In the photos on the website you can't tell exactly so out of frantic worry and to find a solution I posted on here via my phone.
The truth is it's a pretty damn good battery. There is an antenna in the back cover and I'm not really sure why my friend thought there wasn't. Reception seems to be the same even though the antenna is bigger? Or maybe its around the same size if the stock back cover has it hidden in the plastic. The Mugen Power back case covers it with black tape. That aside, the cover feels fairly sturdy, though it could be improved a bit. Maybe some self modification would resolve that issue. It makes a bit more noise when you squeeze it than the stock cover but it doesn't feel like its going to come off or fracture.
As for the battery it seems to last me on average 40 hours before I feel the need to charge it. I'd say it isn't used heavily, more like my old phone where I just sent texts all day, called a few people and listened to music for a good number of hours. The longest I've had it go was 57 hours after letting it completely die. All in all I am quite satisfied aside from a few minor complaints about the case.
Once again I apologize about this, I jumped the gun. Also, the website I purchased it from
http://www.pdaphone-battery.com will deliver if you order from them. I was worried it was a scam site since it looks extremely ghetto and no confirmation email or tracking number was sent to me after purchase. But as I said the shipping was speedy and they did send me what I ordered. They don't use https though which bugged me, however the paying part used PayPal so that was acceptable.