Can't add much to whats already been said regarding your original question except to say views over managed syndicates vary greatly. We're in one and personally we find it good and accept not all decisions will be agreed on, and quite often the management company could do better. It's an almost take your 4 weeks and not having to worry or sort anything else out (almost!). Just for the record we have met a number of people on self managed boats which they have mostly all said works very well for them (less cost but more work/organising). You pays your money and takes your choice! I would guess thats it's more important to get on reasonably well with fellow syndicate members in a self managed group than say in ours, where we have the management company as a buffer zone (we don't really need to know the other members at all!)
For Info, if you didn't already know, there is a useful web site that lists a wide range of shares available, both management companies and self managed syndicates. Link below;
https://www.boatshare4u.co.uk/boatlist.asp
Also if you can wait until May 2025 there is Crick boat show which has quite a few of the management companies exhibiting, which may be useful if you want to chat/compare? They also usually hold several open days themselves.
Best of luck with whatever choice you make.