Yes, I’ve actually already tried the Geekria pads 
And for reference, I have only tried the “upgraded” version. I asked TTVJ what the difference was and he said: “The flat pads and the deluxe are the same pads but the deluxe have been treated and sound more open than the untreated pads. So yes, they do look the same but they do not sound the same.” Since I’m a sucker for snake oil I just ordered the “upgraded” version. So my comments below are with regard to those.
Comfort: Geekria are much softer and immediately more comfortable. The TTVJ feel like new stock Grado pads, rough. I’m assuming they’ll break in over time. It really didn’t bother me. Something I definitely noticed is the Geekria are much more comfortable when wearing glasses (as I tend to do while working and listening). The TTVJ are pretty rough with glasses on.
Sound: (I’ll do my best here, I’m not a particularly experienced reviewer) Geekria have a more noticeable impact on treble. If you think your Grados sound to bright, these will definitely help. The low end I thought was comparable between the two, maybe a slight edge to the Geekria having a warmer overall sound. I attribute most of this difference to the size of the opening. The Geekria cover the outer rim of the monitor. Whereas the TTVJ do not cover any of it. I suspect if you cut the Geekria pads back the sound would brighten up. I never tried that.
I like the detail in the TTVJ, much closer to the L pads in that regard. And doing an A-B comparison with Geekria I felt like the Geekria were muffled slightly. Part of what I like in my Gardos is the clarity, so the TTVJ were the winners for me. Compared to the L pads the TTVJ really bring up the low end, really nice improvement in bass response. Absolutely no sound stage! Borderline negative soundstage - all of the instruments feel like they are in your head, between your ears.
In the end, I’m running with TTVJ pads and really enjoying them.