*most* residential AC compressors, the expensive part in the unit, are made by Copeland. Looks to me like Copeland makes compressors for both Brant and Heil residential AC units. I can't tell you 100% that this would be the case between the 2 you're comparing, but it's a fair bet it would be. Ask your contractor if they have the exact same compressor or not, he probably knows. Make sure the tonnage is the same. MOST importantly make sure the warranty is the same on the Heil as it is the Bryant... double check, is it just parts, or parts AND labor on the warranty cause that'll save you the most in the long run if you do have any issues. From there you want to compare the chassis, are they both just as rugged? Do they both have a hail guard, etc. The link below as a few tips as well.

good luck!
Bill D

Here is a link that might be useful: AC Purchasing Tips

Ask the contractor to give you a proposal for both. Have him include the model numbers of the components. You will get comments as to whether the Heil and Bryant components are similiar in features.

Any reason why you are requesting a conderser, coil and furnace with a rating of 16 SEER?