Bringing it up with a partner
The conversation is usually shorter and less awkward than the version people rehearse in their heads. What makes it go badly is rarely the subject. It is the framing.
The rehearsal is worse than the conversation
Most people who have not had this conversation have run it mentally a dozen times, and the version in their head involves explaining, justifying and defending. In practice it is usually two sentences and a pause. The reason the rehearsal is worse is that you are imagining being asked to defend a preference, and that is rarely what happens. What usually happens is that the other person has thought about it too and simply has not said so.
What the hesitation is actually about
It is worth knowing what you are likely to be up against, because it is not what it sounds like. The common worry is not "this is weird". It is "is this because I am not enough", or "am I going to be asked to do something I do not want to do". Those are different problems, and they need a different answer than a defence of the product. The useful thing to say is that it is an addition rather than a replacement, and that nothing is being asked of them that they have not agreed to.
What makes it go badly
Bringing it up in the middle of an unrelated argument. Presenting it as a solution to a problem they have not said they have. Having a specific product already chosen and ordered, which turns a conversation into an announcement. And treating their hesitation as an obstacle to get past rather than information about where they actually are. Any of those turns a two-minute conversation into a much longer one that is harder to come back from.
Practical framing
Say what you want rather than what you think they should want. Keep it specific and small: a thing you would like to try, not a change to the relationship. Do not have the product in the room the first time you raise it, because a box makes it a fait accompli. And leave an actual gap for an answer, which sounds obvious and is the part most people skip when they are nervous.
If the answer is no
It is worth taking at face value the first time rather than negotiating, because pushing turns a no into a position that has to be defended. A no to a specific thing is not a no to the conversation, and most couples come back to it later once it has stopped being a surprise. If it is a firm no on the whole category, that is information about compatibility rather than a problem to be solved, and it is better to know it than to keep circling it.
More guides
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How to read a product listing
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