He also mentioned a 5% discount code provided by VR Flight Sim Guy here. If you use it, please consider liking it and maybe subscribing to his channel.
(this was a couple of months ago, I don’t know if it’s still valid: try it and find out!)
I ordered the dual lenses (they didn’t have the single at the time) and they took about 2 weeks to get to me in the US.
Overall, I’m quite happy with them!
They do NOT come with instructions so here they are: take off the ‘comfort kit’. Lay the lenses on top of the headset lenses. Put the comfort kit back on, adjust and play, lol. The issue is that there isn’t really any ‘mounting’. They just sit on top of your lenses and are sandwiched in between the lenses and the comfort kit. You can slide them around a bit afterwards but they stay in place pretty well! After loosing my initial distrust of the placement, I don’t even notice it anymore: the ipd’s line up fine. However, since they have it now, I would go with the one-piece.