is it OK to replace just one front tire if the car has only 900 miles on it?

Got my new A4 and after just 900miles I got a small scratch on one of the spikes of the left rim. Rather than fixing it (not sure where and how much but I've heard it can be done) - I thought I can just put the spare on.
The spare being identical tire with the same rim and keep the scratched rim/tire as a spare.

Is 900miles too much of a wear on the front tire that replacing only one would affect the ride?
ANy other issues I should be aware of?

Thanks!

If you assume normal tire wear, 900 miles works out to be less than 3% of the life of the tire - you could scrape off that much rubber in a single flat-spot tire lock-up...

Unless the tires are directional, you could be rotating with five tires anyway...

I was pleasantly surprised to find an identical 18" Conti and wheel in the trunk of my new A6 S-Line. I actually prefer 17" wheels and now have five pristine 18" wheels and tires sitting in my garage waiting for me to post in the classifieds...

Best
Eric

My A4 2.0T came with 17inch all season tires - I am looking to get a second set; 18inch rims with some high performace tires for the summer....I am in NJ....if you live somewhere in the area...

Click my e-mail option - I am in the Boston Metro area - work in Boston - live on Cape Cod..

Best wishes
Eric