Canister filter vs. hang-on-back: which should I buy?

Across the reviewers we read, canister filters win on media capacity, quietness, and suitability for tanks over ~40 gallons, while HOB filters win on price, simplicity, and ease of access. Specialist subreddit consensus leans canister for any tank over 40 gallons or with heavy bioload; HOBs remain the default recommendation for smaller community tanks.