Hello GardenWeb'ers!

My unit, installed in '94 is leaking badly and rather then try to save her I've decided to buy a new unit. I've gotten a bunch of quotes and narrowed it down the following three.

Unfortunately I know close to nothing about HVAC and could use some help narrowing it down a little further.

Option 1 - $3,218
Carrier COMFORT 16[Up to 16.5 SEER] 24ABC6
Install and level on existing brackets or new pad if unit wont fit
Install 3 ton R-410a N-Coil
Install new line set (brazed connections)
All other necessary sheet metal, electrical, and materials to complete
Vacuum, leak check, charge and place unit in service.
Comes with 20 year parts warranty, 20 year labor warranty, 10 year compressor warranty

Option 2 - $3,350
Trane XR16 [16 SEER]
Install and level on existing brackets or new pad if unit wont fit
Install 3 ton R-410a A-Coil
Install new line set (brazed connections)
All other necessary sheet metal, electrical, and materials to complete
Vacuum, leak check, charge and place unit in service.
Comes with 15 year parts warranty, 15 year labor warranty, 10 year compressor warranty
*Only company that did the j load calculation

Option 3 - $3,100
Day & Night 16 SEER CXA636GKA (Deluxe model)
Install 3 ton R-410a N-Coil
Install new line set (brazed connections)
All other necessary sheet metal, electrical, and materials to complete
Vacuum, leak check, charge and place unit in service.
Comes with 20 year parts warranty, 20 year labor warranty, 10 year compressor warranty

Last, but not least I live in Chicago-land and my furnace is about 2 years old, it was installed before I bought the house, and is an Armstrong Air.

I appreciate any and all help and if any additional information would be useful please don't hesitate to ask!