So, keep in mind I am approaching this response more from the perspective of a US Based, SAR ops individual, and hoping that this hits on some of your last points. Oddly I’ve been working on a blog write up on exactly this topic for the past two years. InReach vs Spot, vs HAM. As you call out though it’s hard to find data other then customer reviews and antecdotal evidence. At the end of the day I think I refer to the PLB option as a “solution to a problem that does not actually exist” especially if you are already a HAM. It is true that there are some areas “out there” that not even APRS is an option, and PLB does make sense, but I would say for the large majority of the SOTA outings we go on ham bands will have you covered. I have no clue if the results would be remotely similar on other parts of the planet, and advise you to reach out to those on the ground in those areas. I tend to stick to high traffic areas when activating internationally.
TLDR: it’s a cool tool, it can be an expensive one, it serves a purpose, but as a HAM you already have the great majority of the options a PLB offers you.
Since you called out having the option to communicate with a responding SAR team via the TXT option, you already have that as a HAM. Your HT is that method. Most SAR teams outside my local coverage area I have interacted with do actually have Ham Ops on the team, even if they are there just to provide technical support and some jurisdictions do monitor local repeaters and even citizens band (big in areas with jeep trails). From what I have seen in the W6 and W7N scene SAR teams would rather have voice comms with the subject instead of hoping the txt gets received and responded to. (which btw, if you are on a SAR team elsewhere in the US please reach out to me on DM, I do have questions for you). Looking at your activation history, I would check out GEMA or NCEM or any statewide emergency services organization website, or just reach out to the local ARES contacts as well to see what may be there.
I have heard of folks who actually include their callsign in their outbound message on their PLB which in that case, the responding teams may try and reach out to you on Simplex. If the approaching team is a hasty team they would rather have voice comms with you so they can start relaying back to command post what other assets are going to be needed to support your situation. (Much faster information flow)
https://www.radioreference.com/apps/db/?aid=7742. Is the list of national emergency use frequencies VTAC11 is used…a lot… While I do not personally endorse this, if you have a Baofeng, you already are open on those frequencies. YMMV, but they might be willing to communicate with you on that frequency. I’ve had the “and what if I come up on a subject, or I am a subject in the BC and 911 is not an option” with my SAR coordinator. The response was basically “get on local county DISPATCH, and avoid the ham bands if you can, however if you have to use the ham bands do it”.
I get the tech fun factor and PLBs are a fun new toy/tool, but that said it’s just one more tool in the tool shed. In the mentioned blog write up it literally comes down to your level of comfort (and the level of comfort of those you leave at home) and the fact that a HAM license is 15.00 for 10 years, and somewhere between 300-500 dollars for an HT that includes the features that would put you on par with a PLB (APRS). The PLB unit runs about that same amount, unless you roll your own, and then as Andy called out the cost to use over time can reach to the sky pretty quickly. So do pay attention to your plan/usage.
It does also boil down to the comfort of those you are leaving at home and one other thing to consider there is having and communicating a proper plan with them and I did teach my wife how to follow me on APRS. I always print out a smaller scale map that includes my intended route, potential timing (research the münter method if this is new to you) and other specifics like my call sign, and frequencies I will be monitoring while out there. My general rule is “I’ll be home, or will check in by such and such time, if i’ve not by bed time then start the troops”. If the home front had to call 911, they have all the information responding services needs to get to me quickly assuming I stuck to my original plan.
It’s a fun topic for sure, and everyone has their opinion, and I continue to be surprised by all the hams that resort to PLBs given that we have the tech in our hand already, beyond the “it’s cool fun tech that I want to play with from a tech nerd perspective”