It may well be that the answer will be influenced by the answer to rtbiscuit's question about what wheels you are running.
I haven't personally had the Falkens but I have read about 100 pages from various sources about the tyres you can get for 18 inch wheels for the 350Z and it would seem that if you are after a cheaper tyre, the Falken is highly regarded. Some people have a different view but given that you have said that you will be driving on the road within reasonable limits, I expect that you would find them highly acceptable.
I personally have the 050As and favour the idea of getting the very best tyres you can afford (I would have got PS2s but couldn't afford them).