I have a set of Manley valves I was going to use to rebuild a set of 906's, 2.14 / 1.81

They are Race Series Pro-Flo necked down valves.

Should I have the shop put in exhaust valve seat inserts ?

I don't know if it matters much for longevity on the intakes, but on the exhaust side, maybe so ?

If you use hard seat inserts, what lasts longer, the seat or the valve ?

In my case I'm using a mild hydr cam with light spring pressures, but I'd like the valve job to last.