It is legit, but I have a hard time recommending it.
Placed an order at the end of april for a keycool with reds and some black pbt blanks. After payment, I received an error on the site. I immediately filled out the contact form and waited.
On checking my spam folder the next day, I found an SMTP error message telling me the email to ohmykb was "administratively denied". The message did contain the ohmykb email address, so I sent him an email explaining my problem. Got a reply to my email very quickly; my order status was changed to processing and all seemed well.
Fast forward a week and my order status was still "in processing". I emailed him to ask what the status was, but never got a response. About a week after the mail, I sent him a pm on deskthority, again asking what the status was. I got a speedy reply saying he had been very ill and my order would be shipped asap.
Order got shipped, like he said, but I didn't receive an email containing the tracking number. I presume the same issue that plagues the contact form, also impacts all other automated emails.
I pm'ed him again on dt asking for the tracking number, but never got a reply.
A week after the last message, my order finally arrived. A full month after ordering (shipping went a LOT faster then expected), but my joy was short lived. The keycaps he sent were white blanks instead of the black ones I ordered.
So once again I turned to dt. Sent him a message in the beginning of last week, but still haven't got a reply. Also tried on skype, but got ignored there as well.
At this point I just decided to cut my losses. I can live with the delays but the lack of communication is what really ticked me off. It feels like you're talking to a wall at times and I refuse to keep sending the same message over and over, in the hope he will reply.
Luckily, white blanks on a black filco don't look half bad.
If you happen to be a bit of a masochist, you won't find a better shop.
If you want speedy processing and clear communication, look elsewhere.
Please keep in mind that the above is my personal experience/opinion so your mileage may vary.