I don't see many PFD that have crotch straps. My experience is the kids and I are all fairly uncomfortable in the water as the jackets float up to our armpits.
My favorite PFD was one made for water skiing that had a strap for each leg. Sadly it got stolen. The toddler PFD also had them.
Is the thinking now that crotch straps are too big an entrapment hazard? If I had to take a long swim I'd sure rather have one than not.
Some internet research shows that most of the name brand pdfs have the option to add crotch straps. NRS calls them leg straps. So, if you find a pdf you like, search their website for crotch straps and you may find them. Here is an example (but there are more)
(I also had a child and her pfd had crotch straps.)
You also might be interested in the Stohlquist Rocker Pfd, which has:
- Cross-Chest Cinch for Zero Ride-Up
The innovative Cross-Chest Cinch harness, found only on Stohlquist PFDs, offers the most unique fit of any PFD, by keeping the vest down & in place, to eliminate ride-up. The "cinch" prevents and eliminates chafing on your chin and underarms caused by annoying vest ride-up.
That might keep your pfd in place.
Clearly the kind of pfd you want depends on what kind of water sports you do. If you are doing calm water, no ww, then a lighter weight pfd is probably good enough. If you do WW, or paddle on shoulder seasons, you might want something more substantial.
I have not found a pfd that has a knife sheath rather than an outside lash tab. I don't know where my instructor got his. I should have paid more attention.
My current pfd is from Stolquist and does not appear to be available anymore. It is styled to accommodate a woman's figure.
I also have an old Extrasport that I really like.
A couple things to keep in mind when shopping for a pfd.
1. Check the amount of floatation. Most are around 16 pounds. One I looked at was 18 pounds. This is enough to help you float but it will not turn you over or keep you floating if you are unconscious.
2. Check how much it weighs. Some are as light as 1-1/2 pounds. Others are over 3 pounds. And that is not counting the gear you put in it.
Overall, noted again and again, is: The best pfd for you is the one you will wear.
It doesn't matter how great the pfd is if it is sitting in the bottom of the boat when you swim.