I think I have written this in another thread, but here is my $0.02:
My 2020 son did HF in NY the summer before his junior year (2018), and SB in Bradenton that fall. He did Showball in Boston the summer before his senior year (2019). HA recruiting really doesn't start until players have three years of HS grades available, so don't go to one of these events before you are a rising senior and expect to get seriously recruited. But if you can afford it, I think it's worthwhile to attend one of these camps as a rising junior. Going "early" gives a player the chance to see what the events are like, to talk with some coaches and maybe lay a foundation for an email and telephone correspondence during junior year. For this purpose, HF may be the best bet, since it is MUCH easier for players to meet coaches there than at SB. HF Day 1 includes some time when coaches are available and players are invited to meet and talk with them. HF was my son's first time dealing with college coaches face-to-face, and the experience of introducing himself and carrying on brief conversations was very valuable. I think that was great preparation for the phone calls, texts and meetings with coaches during the following spring and summer.
HF is very well organized. You are given a schedule showing which coaches will be on which fields. HF also includes several informational talks for players and one for parents--these have some good info, especially if you are new to the process.
SB does have head coaches. This has to be a good thing, but I don't know how big that advantage actually is. Not surprisingly, the camp before my son's senior year was the most productive one he went to, and led to him committing to the school he's attending next year. That camp happened to be SB, but I think he would have gotten similar results from HF. Both camps are great for being seen by HA schools. There is a lot of overlap, but it is worth putting the lists of colleges attending side-by-side and determining where you can be seen by the coaches you are most interested in. Neither camp had every school my son was targeting--for him, SB had a slight advantage this past summer when it came to having most of the colleges he wanted to be seen by.
My son also decided he preferred SB's format, because he said he didn't want to attend the HF informational speeches again. (He's 18 years old and knows everything...) SB is almost all business--you go, you play, and you leave. Unless a coach happens to be assigned to the dugout where your kid is playing, at SB it can be difficult to find them. (Of course, if a coach knows he wants to meet a player, the coach will make sure they talk.) But keep in mind: your kid is highly unlikely to get recruited unless he has been in touch with a school via email beforehand and they are expecting to see him. Shaking hands with a coach at camp is worthwhile--it's good for coaches to put a face with the name they have seen via email; but the meet-and-greets at HF are not a substitute for doing the legwork to get recruited.
In my experience HF is definitely better run. At both SB events we attended, scheduling was a little chaotic (long story). Most importantly, my son was scheduled to pitch at 8 am on Day 2 of SB in 2019. They decided to start the game early to get a jump on the day, and so they literally put my kid on on the mound at 7:45 a.m. after only letting him throw about five pitches on flat ground to warm up. He never really got loose--and his velo was a full 5 mph slower than it was an hour later when he pitched his second game with an actual warm up. The college he will be playing for this fall saw him pitch in game 2. My son did hear from one or two coaches who saw game 1, but most of the interest he got was from coaches who saw the game he got to warm up for...
I like SB and I recommend it. But I do think HF is more organized and provides some worthwhile experiences beyond just the games. On field, the camps look very, very similar. You can't go wrong with either one, and IMO the schools attending each camp should be the main factor in your decision.