Try the ones from Maximum Motorsports. They're a REAL nice piece, probably the best i've seen. Theres also some on Ebay from UMI Performace that are a real close 2nd to the MM's.
I read through the instructions for the MM ones. Seems like they take a while to install with all those gussets and everything. How long should they take a reputable frame/body shop to put them on? Where is the best place to get them installed?
The Steeda kit does come with the cross braces that bolt to the seats. They come in bare steel part #555-5245 or zinc plated part #555-5246. I put the zinc plated ones on mine. It took the shop about 1 1/2 hours to do the job. They also come with a plate for the torque box area that joins the 3 separate pieces into one. They are a very nice package. The prices are $129.95 and $159.95.
I noticed a big difference with my MM full length subframe connectors. I dropped my car off at the muffler show at 8am and had it back by 3pm welded and painted welds. (they just worked on my car on the side) I was charged $100. Good luck.
I think im going to go with the steedas. They are the same price as the MM ones plus they are zinc coated and their gussets are already attached to the seat bolt reinforcements which means less welding.