If they had good results with this dealer, you have a much better chance yourself. There are way too many careless dealers and good dealers with lousy help - you have to be careful. There are many shortcuts that can be taken with the installation of new equipment that homeowners don't understand. Their are issues like sizing, brand, efficiency, how it installed - that play an important part to the operation and comfort the system produces. I'll cover those issues next.
Most brands are similar but some are decidedly high end and some are low end.
You can't always tell by the price quoted. Best bet is ask the dealer why they chose the brands they did, how long they've had them, who wholesales them locally. Neither brand is well known but both are above average in quality from what we see of the industry. We feel that is more important than name recognition. It helps to stay with the same brand so your techs get to know it.