Some thoughts from my "first time buyer" experience back in 2001.
There wasn't much available in a prebuilt roller version back then. Some mfg built their own in house, but those pretty much built to order, except for Superformance which was available from a dealer's showroom floor or built to order (color/options).
I started my "due dilligence" back in 2000, and narrowed down to ERA or Superformance. Factory Five was in the running, but my calculations showed that it would cost close to the SPF and ERA after I figured in new components and the time to build, and there still was a big difference (no fender liners, rough fiberglass under the rolled edges, ect). I looked at and drove several cars from different manufacturers. For me, the SPF and ERA were in a class of their own back in 2000-01.
I went with Superformance, and have never regretted it. The resale is there (although I will probably never sell), the build quality is excellent, and I have driven mine more than most - over 80,000 miles in all 4 seasons including snowy upstate NY roads (with which you are familiar) on a daily basis for several winters. The owner's group - SCOF (and their many events they put on) is a huge plus for me. Check my gallery for some winter driving photos
I started with a Ford Motorsports 351/385hp crate motor, and am now running a Roush built upgrade of the same motor. I do love the sound of a SCREAMING small block, and my next motor will be more of the same. Lots of power is nice, but with huge HP numbers you can't get on it and stay on it for long on the street - if you want to keep your license. I will look for decent TQ numbers (450-500) and a working 8,000rpm redline for my next motor.
Look at the cars. Drive them - if possible drive a couple of cars from each mfg you are researching.
Everybody is looking for something a little different in their Cobra. You mission is to find out what works for you, and ultimately what YOU want!
Have fun :-)
Jim Kellogg