The Opinionated Diver

Get jet fins (the model, not necessarily the ones from ScubaPro), because:

• Stiffness gives you more bang for your kick
• Stiffness also aids backfinning*
• Vents give you more precision
• Vents may give you more thrust (opinions on this are divided)

Exceptions to the rule:

• Many cave divers prefer skinnier fins
• If you’re a minimalist traveler and require the absolute lightest fins (although there are some pretty light jet fins out there these days)
• If you can’t frog kick ← this is a non-argument; get an experienced instructor to show you how to (if they can’t then they’re not experienced)

If you do go for regular (non-jet) fins, then be aware that much of modern/fancy fin-design appears to be aimed at counteracting poor finning technique, such as “overkicking”**

* Backfinning: reverse-frogkick for backwards movement
** Overkicking: basically kicking your fins too hard

Open vs closed heel

Open-heeled fins are made to be worn with boots; closed-heeled fins are worn with bare feet.

If you’re diving in a drysuit then go for open-heeled fins.

If you’re diving in a wetsuit then buy some boots and also go for open-heeled fins. You’re less likely to lose an open-heeled fin than a close-heeled fin and walking barefoot is way less fun on rocky beaches.

Always go for open-heeled fins.

Straps

Get a fin with a strap that has something to hold onto when you pull them off.

Weight

Before you consider the weight of your new fins in your suitcase, consider their weight underwater, and how it combines with the distribution of gear, suit, muscle-mass and fat over your body.

Some dive stores will let you try out a pair of fins in their pool or pond before you buy them.

Notes on specific makes and models:

• Apeks RK3 – The RK3 is a great choice but get the RK3 HD; the regular RK3 is quite floppy and not great in strong currents.
• DiveRite XT – Fine if you’re not going into caves or wrecks. Cave-line tends to get tangled in between the center- and outside strips.
• split fins – For the love of God don’t get split fins. Supposedly undoes averse effect of overkicking (debatable). Only type of fins in which backfinning is near-impossible. Don’t rely on your fins to compensate for your poor finning technique; get help. The one redeeming value of split fins is they apparently help people with knee/ankle problems (split fins put less stress on the joints).
• Hinged fins – Supposed to give extra thrust when you’re “overkicking”, doesn’t appear to do much when frog kicking.
• Freediving fins – You could use them, but I wouldn’t. Great for strong currents, but your buddy is 500% more likely to get hit in the face with your fin. A big NO for wreck-penetration or any other overhead diving.