Really Newbie here
(especially after the information overload in these forums )
Probably no right answer here, but i figure i'd put the question out ...

Replacing 2 3 ton Carrier units due to leaks, condensation problems, etc. Spending on average > $500 every year per unit.
Done with that.

Got quotes from a recommended installer.
Trying to decide between Lennox XC21 vs Trane XL16i with the filtration (mainly to take advantage of the rebates).
Sold on the new refrigerant.
Sold on the 2-stage.
Sold on the warranties.
Don't mind the higher SEER rating (20 on the Lennox) if it does make an impact to the wallet.
Not sold on the price - but it is what it is.
Neigbor is very comfortable with his Trane - but reviews here tend to lean more towards Lennox (might be my perception).

Not writing a thesis on HVAC - just need trouble free, efficient units, period.