I had exactly the same behavior, glad i wasn't the only one. Was thinking of a problem with the BD Drive, but when i installed webman mod. Everything was fixed and running as it should. I had installed the full version. And i have tested with 2 hard drives, the behavior was the same, After qcfw...
Update : no more slow downs or lags, a pin of the ribbon from the BD drive was broken, i fixed it and now everything is running smooth (game ftp transfer are also slightly faster than in my other FAT ps3)
No problems with this, everything IS running well, that was just a little bit different as my others cfw PS3. Just wanted to be sure it wasn't a hardware problem or hdd problem. Gonna continue the tests but it's promising !
Successfully done the modchip installation and qcfw. Managed to put the modchip on a accessible zone in case of reflash or modchip disable.
Just a remark, i remark the menus and app launch or game launch are a little bit lagging, il tested with 2 hdd and with hen no problems but with qcfw it's...