Price point was €119, German layout. I obviously plugged it in immediately, and I absolutely love it over my old G15 where the keys became really stiff after 1.5 years of use.
There are some things that are... irritating so far. I used to move my keyboard around all the time to bring it from "gaming" to "typing" move and back in the blink of an eye. The Celeritas seems to be glued to the table. Second is the dreaded space bar. If you type normal with both hands, and hit the space bar in the middle, it is absolutely awesome. However, when playing with one hand and jumping or whatever, you usually hit it at the edges, where it feels completely different than the rest of the keys, kind of like my old G15 space bar. Not very crisp.
At first I also thought that the shift key layout would be trouble, but it appears to be none (the left shift key is just slightly bigger than a normal key).
The awesome things are obviously the awesome low resistance. Its not like I dreaded that as soon as you touch a key it registers, but when you move your finger across the board they sink in a little. A bit more pressure, and they register. Thats fucking awesome! Wow, lots of awesomes. And the sound. I absolutely LOVED the sound at lan parties when someone was playing broodwar. All the cool keyboard noise. Its calming and soothing for me. And now my keyboard makes the same noises. I have brown switches, and obviously when the keys bottom out because I'm pressing them with way too much force (but so much less compared to my G15), so I guess that issue will fade over time when I get used to the low resistance and only have the sound when it should be there - when playing!
Btw, the f-keys are perfectly lined up with the arc of the board. So when I move my fingers up from the numbers, the f-keys are exactly there, at the exact height intuition tells you they should be. Hopefully I can implement more f-key usage in my play now.
Also, yeah it's heavy. I could probably kill someone with it. Thats another thing to get used to, to find a keyboard position in which I can play AND type comfortably at the same time.
Sadly, I have neither a PS/2 slot nor progamer APM, so I can't really comment on the response time enhancements.
However, I really don't know how playing games will be with the space bar. It doesn't seem that bad right now, but I will give it a try for about a week, and if it is unbearable I'll send it back. Hopefully not though. I'm already converted to the cult of mechanical keyboards.
Have a nice day!