Accent spark plugs

Quick question. I have a 2004 accent and I am about to come up on 40K miles. What is the typical life span of the factory spark plugs? Also, I do about 70 miles of freeway driving 4 times a week? Would it be worth upgrading to platinum plugs? I know that in higher end cars, they are mandatory but will the improve the little accent as well? Mainly gas mileage?

Thank you in advance

I replace my plugs twice a year. But that may be over doing it.

replace plugs every 15000 miles. I use Bosch plugs. A little more expensive but my car seems to like them

I change them every 30,000. Don't bother with platinum tip check get the spark plugs from the dealer.. OEM plugs work the best and you will get hte best milage out of the, I believe they are NKG R

I agree.
Use the NKG that your manual recommends. I bought my 2002 accent with 25K km on it. After a while it started running like crap.
I pulled the plugs out only to find that the previous owner had put Bosch platinums in it and one of the insulators was cracked from top to bottom causing an arc and another one had a small crack. I installed the exact NKG number from my manual and now have 82K km on it and still getting excellent mileage.
I think I will put new ones of the same kind in again in the near future just under general principles.
W.Y.

NGK's are good plugs. I'd run champions once I get my accent and the OEM's require replacement. Standard copper works great. I run them in all my current and previous vehicles (Ford, GMC, Dodge, Toyota), and small engine equipment. I wouldn't get platinums as the long 100 000km change interval seems like a long time, especially if the vehicle isn't driven often. I change the champions at 40K and they still look like they could last another 20-30K. I don't take chances on my maintenance. Every vehicle I've owned generally sees severe service and lasts well past 250K! The accent better last that long...