I’ve noticed some problems when using groupField and hideFirstGroupCol:true properties (I also set loadonce:true)
1) Sorting on columns doesn’t work correctly (rows from different groups get mixed).
2) when editing a row, the field used in groupField is not filled with data.
3) after insert, the “new” row is not placed in the correct group.
4) trying to solve problem #3 I tried to reload the grid to display the updated content correctly, but for some reason it seems the grid is stucked with the initial values (I can see that webservice is being called and returning the updated values).

here’s the jsfiddle:
http://jsfiddle.net/L7tr0g5a/1/

To reproduce problem #4:
1) after clicking on add click on fill values and then on save.
2) Since the row is not placed in the correct place use the button to reload grid and get the “updated” data. please notice that in this step I had to change the url to fetch the data since I wasn’t getting the updated response (i tried to update the values of the variable used to simulate the ajax response but didn’t work).

Thanks in advance!