Best Primer, come and tell me what one you use

[Deuce]

I use smashbox but would like a cheaper one if possibe.

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I just bought the new No 7 primer. I've never used one before but I can definitely notice a difference. My skin looks smoother.

I tried the No7 Protect and Perfect serum for the first time the other day (behind the times I know). Don't know how it is as a serum but have to say it was amazing as a primer. I know it is meant to be a 'serum' but can't see the difference between it and a primer to be honest. It sits on top of the skin just like primer and it smoothes just like primer.