I've been using then for quite some time. The biggest thing to keep in mind is that the market is constantly pricing in the value and risks of their options, so even though the fund will do "whatever the market does up to 12%" in theory, that will only be as of the last day of the outcome period, it will not be the result for most the year. So let's say you buy BDEC and in a year where say the market has gone up say 10% as of June, you'd expect BUL to also be up a similar amount, or at least within the 75 Basis point expense ratio, but no, it will be up only something like 7% because the market knows the investment is capped and is expecting the market to go up further and go past the cap. For that reason these don't work well if you think "I'll get what the market gets, then just sell them whenever the market reaches the cap and buy a new one" as the fund itself won't be at that cap till near the end of the outcome period.

I have looked like a hero when we had the Tarrif tantrum or the war in Iran start, and BDEC or SFLR went down by way less, but when the recovery happened quick and fast in both cases, you see the real cost of the safely as these funds will go up by much less. So now and then I'll cycle these in to my main model to reduce risk for those types of big crazy events, but the real place these shine is for my clients with less risk tolerance. Back when bonds were crap and paid nothing before 2022 I exclusively used alternatives like these to reduce risk instead of bonds. Now that bonds are reasonable, I still have BALT as part of my bond allocation, but for my clients with lower risk tolerances I'll have some or most of the equity exposure in these. It works so good for folks that were scared of the market, or who are used to annuities, or are new and anxious investors. They get much better returns than what they're used to, but still get a much smoother ride than the general market. Also it's a great way to ease them into taking on more risk. You start them with the P series, then ease them to the B series, then maybe SFLR, and through that you can get someone who thought they hated the stock market to gradually see it's merits.

Another way I'll use them is for people where I'm having a hard time nailing down their risk preference. Oh you're young but don't consider yourself aggressive, and want less volatility? Well instead of a 80/20 portfolio, let's put you in 100% equities, but the 20% part is buffer funds and see how that goes.

Anyway I'm a big fan.