I have the We-Vibe 4 and the Lelo Tara, also used to have the We-Vibe 2 as well. So I can kinda give you my opinions.
Firstly, I notice that these couples vibes always get mixed results from different people. With other vibes, there tends to be more of a lean in one direction but couples vibes seem very personal to each person. I've put this down to the fit. We all have different shapes/lengths vulva and we all have certain parts of the clitoris that we like stimulated so...it is about whether a particular toy hits your hot spots or misses/overshoots them etc.
I am still testing the We-Vibe 4 but what I can tell you from my experience is the following:
1) It stays in place. The new design on the We-Vibe 4, unlike the We-Vibe 2 design, seems to ensure that, once inserted, the clitoral arm is clamped (Not painfully) where you want it and the movement as he thrusts inside is minimal. It stayed on my clitoral area the whole time, except once or twice when it twisted away during him inserting. Soon fixed that though
2) The vibrations on the We-Vibe 4 are stronger and more rumbly than on the Lelo Tara. (I cannot compare with the We-Vibe 2 as I got rid of that a year or two ago and obv can't compare accurately without it)
3) My guy prefers the We-Vibe 4. He said, compared to the Lelo Tara and We-Vibe 2, the smaller, flatter insert is comfortable for him (His comment was that he could not feel it. He is of average size and bigger guys may feel it.) He also said he actually really enjoyed the vibrations and could feel them reasonably strongly, again unlike the Tara, the Tara is a little more gentle. His favourite to use together was the We-Vibe 4, for comfort and feeling the vibes.
5) All these couples toys felt a little fiddly and occasionally painful during initial insertion. This is my experience anyway, but I have vulvodynia so when he inserts and pushes the arm up into my vulva, it can be a bit ouch. Weirdly, the ouch goes as soon as his head has popped in and we can have sex as normal.
6) The We-Vibe 4 is ideal for hands free. It stays still and in place, the Tara is too, but it does not have a remote (It's big brother, the Ida, does) I had to hold the We-Vibe 2 still the whole time. This makes the We-Vibe 4 the best for complete hands free overall.
I understand what you mean about the fit and unfortunately that is something none of us can answer because it will depend on your own dimensions. I have not come across one of these couples toys yet, that fits me perfectly. All of them overshoot the sensitive part of my clit. I guess I must be quite short or small down there. The We-Vibe 2 missed altogether and wiggled all over the place (for me) the Tara covers my clit perfectly, but provides a flatter, more diffuse stimulation with shallower vibrations, so I can only orgasm from it when REALLY horny to start with and the We-Vibe 4 has the best vibrations yet, but the slightly curved clitoral arm overshoots my clitoris and comes to rest justtttt below my pubic mound (I like stimulation to the base of my clit) Fiddling with them does not help much in my experience.
The thing is...its obvious they are not going to be perfect. With a bullet, you can direct the stimulation right to that very particular area that you need it and you can control the pressure. These two things either cannot be done at all, or are not easy to do, with couples toys (Just like with rabbit vibes)
I have kind of come to the conclusion that couples toys are brilliant, as long as you are not COMPLETELY fussy with your stimulation. If you can still orgasm with vibrations that are reasonably close to where you would like them, but not quite, or if you are reasonably sensitive and do not need a jack hammer on your clit (Like me lol) then these toys will probably suit you much better than the ladies who DO need a jack hammer, directed to one particular spot or forget it, kinda thing.
If you need any more info about these, just ask and I shall do my best to go find an answer for you. My top pick would be the We-Vibe 4 btw.
x