Just to muddy the picture a bit, I had been running Kaos Froyo through various updates for the last four weeks. I've had a few minor headaches with it, but the biggest for me is that the market just doesn't work like it should (and this has been the same for many versions.) First, I rarely get updates that new versions are available for apps, and often get the notification only when I go into the market for other reasons. Second, when I fire off an update, quite often they get stuck. Either they download and never install, or download and install though the market shows the app as still downloading. It's frustrating.
However, last night I had the worst problem - my phone lagged worse than it ever has. I could barely get it to do anything - even long-press on power took a minute to show the power off menu, and quite a long time to reboot after I chose that option. That was the last straw.
I had ran CELB Froyo for a few days, and that was better, though I really prefer the flashing trackball as a notification over the LED, which you have to manually set for CELB on an application by application basis. Also, after fully charging, the green LED would stay lit after disconnecting power, or at least until I had another notification that lit the LED. A minor issue, but one that I could probably live with; otherwise, this ROM is solid.
Last night, after the Kaos lagg-up, I decided to flash Nonsensikal for the first time. I flashed 7.0, as apparently 7.5 has a problem with the camera. Anyway, this ROM is fantastic, IMHO. It's early for me to say that it is better than Kaos, as I won't know for sure until I go for a few days and do not get the lag issue, the market issue, or an issue that is specific to Nonsensikal.