OK so I have found a decent deal on a Heat pump + install.

The only issue I have is that this contractor is recommending a 3 ton unit versus others that recommended a 2.5 ton, however this is the company who has been installing the HVAC for my particular builders homes for the last 4 years so he is very familiar with my exact model home and its requirements, so I'll trust his judgement on that.

The issue is with the line set that was installed during the construction of the home. It has a 3/4" Suction line and 3/8" liquid line. According to the specs for the heat pump he's installing it requires a 7/8" suction line. Is the 1/8" smaller diameter suction line a real issue? Should I have him redo my line set? Maybe trade on mine? or will it be fine to go ahead with everything as is? Or should I go for a 2.5 ton unit, which was suggested by about 75% of the quotes I got and matches my line set?