Been using prescription lenses since 2016 - I found the best were VR Lens Labs, but they took quite a while to arrive at 6-8 weeks.
I tried some from VR Optician recently - they arrived in less than 2 weeks (both companies are in Germany, but VR Lens Labs ones come from Thailand hence the longer delivery). The ones for my Index were very good, but the ones for my Quest 2 were slightly out of focus and VR Optician were very unhelpful - you know, it must be something I’m doing wrong, because they made them correctly sort of thing.
Then there’s Widmo. I heard some good things about them, but the lenses I got from them were the worst ones - very bad and I never used them. Didn’t get any response from them about that and my optician reckons they put the lenses in at the wrong rotational angle.
Prescripition lenses are imho much better than using specs in the headset, with the added bonus that you don’t have to worry about scratching the VR lenses, plus if you have eye relief, like with Index, you can dial the lenses all the way to max FOV.
Despite the longer delivery times, I would prefer VR Lens Labs - every set I bought from them were excellent (for Rift CV1, Quest, Quest 2 and Index, plus they do a set like glasses, but with an elastic headband so they fit close to your eyes and can be worn with any headset - all were perfect).
**edit: One thing I forgot to mention - the VR OPtician lenses are deeper than the other two, and they were actually touching my eyelashes when I blinked