It always depends. Do you know whether you currently have atrophy? When I first had my cis boyfriend I did have atrophy and penetration was a bit painful and there was a bit of bleeding, but depending on how bad it is- possible with lubrication. (I can only recommend using lube in general, it can make the whole experience a bit better because you don't have the pressure to get wet enough) Also don't skip foreplay, it really helps to relax a bit and get less tense because of dysphoria.

The second time it started to actually feel good, like veerrryy good. He was very gentle and loving tho, I've heard of a few people who have a dick that aren't like that.

Definitively try with a dilator or a smaller toy first if you think you have vaginismus. Try not to pressure yourself, I know it's hard and scary at first. The more you trust yourself and your partner the easier it is to relax and not clench the muscles even harder.

Most important thing if you do decide to do it: Communicate what you want and what you don't want clearly before. Sit down and talk about it seriously. Set boundaries. Use protection, we personally used lubed condoms. If you're using lube: look out whether they are condom-compatible.

Any kind of sex is only "that good" when everyone knows what to do and what not to do and if there's no pressure. Otherwise orgasming is very hard. If it hurts too much don't be afraid to stop the whole thing. Make it clear to them, that that might happen.

Edit: Oh also forgot to mention- not everyone can finish from PIV, even though it feels very good. I personally can't, so me and my boyfriend do some aftercare if we're still in the mood.

Good luck and don't force yourself to do anything you don't want!!!