I have 9 of their glasses, all are perfect. You will not have to send in your old glass if they already have a scan of the one you need.
Please be patient after paying for it, it could take a few months to get it depending how many orders are ahead of yours.
Very important also, Steve has a full time job and travels a lot ( not sure about his traveling schedule with the C-19) and this is a hobby/second job for him.
You will need to have patience but in the end it is worth it.