Both approaches get you to the same collection eventually, but they optimise for different things.
Singles win on cost and precision
If your goal is a completed set, singles are almost always the cheaper route — packs mean paying for duplicates and cards outside your target set along the way. Buying exactly the Mega Slowbro ex you need costs less than opening packs hoping for it.
Sealed wins on experience and long-term holding
Opening a pack has an appeal singles simply can't replicate, and unopened sealed product — Booster Boxes especially — tends to hold and grow value more predictably over years than most individual cards.
The realistic approach
Most collectors do both: open a Booster Bundle or Box for the fun of it, then use singles to fill whatever gaps are left in a target set without gambling on pulls for cards already available directly.
Frequently asked questions
Is it cheaper to complete a set with singles or by opening packs?
Singles are almost always cheaper for completing a specific set.
What's the appeal of buying sealed if singles are cheaper?
The unopened pack experience, plus sealed product's tendency to hold value well.
Can you mix both approaches?
Yes — open product for fun, use singles to fill remaining gaps.