Honda factory filter and factory oil.....
....or, if you are really, really, anal like me, Motul 300v 10-40 oil and Per-Form filter.
But, it really does not matter much, if at all.
As far as the 20-50 weight in hotter climates, that's really not necessary. I'm in Louisiana and use 10-40. The oil weight is determined by the tolerances inside your engine more than the ambient temperature.
Our engines are precision built, by HRC professionals, and the owner's manual asks for 10-40.
Mobil 1 is darn good oil, it is easy to find, and should fit the bill.
Don't over think oil.