Buy direct if you know the track
An experience company buys a session from a circuit and resells it with a margin on top. That is a perfectly reasonable business, but it means the same session usually costs more through a reseller than through the track's own website.
So if the person you are buying for has a local circuit, or already races somewhere, buying that circuit's own voucher is almost always better value. It also means every penny goes to the operator, which matters more than it sounds for small independent tracks.
We have found 17 circuits in our directory that sell gift vouchers or gift cards directly.