I currently will be purchasing a home on long island ny. It has a brand new 2 stage 80% natural gas hot air sytem. I guess they didnt go for a 90% unit since they would be moving. My plan is to add an a/c unit for central air. I am wondering if i should go for a heatpump instead? I know this has been asked numerous times, but i am looking for some opinions.BTW i will be doing the install myself(I have much experiance in all phases of building and plumbing, but i am not an hvac expert) Thanks