Ipecac is fine. That's not a hard item to use, just treat it like you would a grenade launcher in a FPS and pace your shots to make sure they are far enough from you.
In other news, despite breaking the game wide open and getting basically all the items, I still haven't seen Buddy in a Box. The only new item I haven't seen (Edit: after writing half of this post, this was a lie).
Just a bad string of luck in the shop, I guess.
So yea, other than Buddy in a Box, here's my reviews of these items from the last week of using them.
Bozo - For whatever reason I've gotten this item within the first few floors in about 75% of my most recent runs. I've checked and it's not broken and set to be ultra common, so just weird luck. So it's the one I'm most familiar with. The piddly damage up is alright, but the actual effects have only really been noticed once when the random rainbow poop actually saved my life, so thanks for that. This is also one of the best looking of the booster items, even if it's slightly out of theme (it still fits the game fine)
Lil Delirium - Such a fun item. It stays transformed long enough to not be obnoxious, but constantly changing makes you aware of it at all times. I found most of the time it was very useful, turning into Incubus, Rotten Baby or Lil Brim. I've never had the Bob's Brain or BBF transformations blow me up, either, so I don't think you need to be that careful with it. Excellent sprite work on the item, as well. But I'm bias because Lil Delirium was my most wanted item to be added officially, so I'm quite pleased.
Mystery Gift - This is the single most broken item in the game, probably in the history of the series. This and Void makes the old break of Pandora's Box + Void look like child's play. The ability to spawn infinite items from any pool you want but the third or fourth floor. Whoa boy. I don't even know what use this item has being not broken, I guess a free Devil or Angel item is pretty cool. Also a Pokemon Reference is always neat, even if it's just in name only (and the name is an intended reference apparently).
Angry Fly - This is an early game item that I've only ever gotten very late, so I'm not really sure how it's best used. It feels like it's a great item on early floors, but late game it's kind of useless since later chapters have you generally fighting one or two bosses in rooms, rather than a ton of regular enemies. Also not counting towards Beelzebub screwed me out of flying at a key floor where I desperately needed flight. TYRONE PLS.
Black Hole - Another Booster item that I likely found way later than it was intended to be. I guess it's useful? But by the Womb (when I found it) I was already well built and had a useful active (Void with Mystery Gift lel), so I never really got the chance to use this item to its fullest. It was SUPER annoying to use during the break though, since I had to throw every time I used my active, or Sharp Plug wouldn't activate. But that's not a fault of the item, every throwable active would be like that.
Broken Modem - No thank you. Nope. Never again. Not a chance. This gets thrown into the "Cursed Eye" pile of "do not touch, ever, there is no run where this works"
Fast Bombs - Fast Bombs + Golden Bomb is comedy. That's about all there is to it. It's a basic item that does what it says on the tin and has its uses as more of a convenience than anything useful in combat. Not every item added needs to do 10 thousand things all at once. The game needs basic items like this for balance.
Buddy in a Box - From what I've seen on streams, this item is decent. The Buddy can often have good attacks and great tears, and it's finally a purpose for the hundreds of co-op babies they keep adding that hardly anyone has ever seen. Would I take it over other shop items given the choice? I'm not entirely sure.
Sprinkler - I guess I lied when I said Buddy in a Box was the only item I hadn't used yet, because this is another one. I've never even seen it spawn. Reddit seems to love it, so I guess it's pretty good. Seems like an excellent item for Greed mode, except it isn't in the Greed pool (none of the Booster items are probably as an oversight). Oh well.
As far as trinkets go
Hair Pin - This is Isaac and Appollyon's new best friend. Free full charge every boss fight? Yes please. The sleeper hit of the booster.
Wooden Cross - Seen it, never picked it up. Seems kind of niche, but I'm not going to throw it away if I can smelt it or something.
Butter - This seems like an item meant for Plus' release, since they added all those reroll machines into empty secret rooms. I'm disappointed at the graphics on this one, though. It's kind of ugly for being an item made by Edmund. I'm pretty forgiving on the graphics of the other Booster items, but this one has no excuse.
The Draw 3 card is useful, the other ones are "eh" although that might be because I don't have what they do memorized so I just use them whenever. They likely have better uses than using them in empty rooms or rooms with enemies that I didn't need to use a card against.