Hello if it has been problem free or few issues i would say yes. The one thing you want to keep in mind is the furnace is not a big deal relocating wont hurt it. however the ac unit has to be ( coil) has to go as well and if they don't replace the line set and clean the lines and coil you often have issues. Now any good ac guy will know to put a filter drier in line and do a triple evacuation. This will make sure the system ( cooling) continues to work.
As with anything new is better and the additional cost of the new equipment may be worth your piece of mind. Expect 20 years out of a system installed correctly. If you were to replace the heating and cooling side you could qualify for the federal rebates and any local rebates depending on the equipment which could off set the cost. Weigh your options, quotes are typically free.