IMHO, the SSTab control is a very solid control, and I get much use out of it. However, it does have one annoying bug. When the TAB keyboard key is used, the SSTab control can pass the focus to controls on tabs that are not the current tab. In other words, the focus just sort of disappears. This is a major annoyance, and I have fixed it with the following class module. Also, an issue with combo-boxes is also corrected. See comments.

Code:
Option Explicit
'
Dim WithEvents tabCtl As SSTab
Dim frm As Form
Dim TabStops() As Boolean
'
' A primary purpose of this fix is to correctly control the tab stops.
' To make the appearance of tabs, the SSTab control simply moves the controls out of view.
' An artifact of this approach is that the controls are still able to get the focus when the
' user uses the TAB key.  The following code corrects this problem by appropriately turning
' on and off the TabStop properties of the controls as the user tabs from one tab to another.
'
' Another problem has to do with ComboBoxes.  When changing to a new tab, dropdown comboboxes
' will have their text selected.  The combobox will not have the focus, but their text will be
' selected.  The primary problem with this is that it right-justifies the text when there is more
' text than will fit in the textbox portion of the combobox, and this is confusing to users.
' This problem is corrected in the following code.
'

Friend Sub SetTabControl(TheTabControl As SSTab, TheForm As Form)
    ' Call this in the form load event.
    ' The BogusTextBox must be on the form (anywhere), and NOT the SSTab control.
    Dim ctl As Control
    Dim ptr As Long
    '
    Set tabCtl = TheTabControl
    Set frm = TheForm
    '
    ' Store the true value of the TabStops.
    ReDim TabStops(0 To frm.Controls.Count - 1)
    ' Not all controls have TabStop property, so we must set error trapping.
    On Error Resume Next
    For ptr = 0 To frm.Controls.Count - 1
        TabStops(ptr) = frm.Controls(ptr).TabStop
    Next ptr
    On Error GoTo 0
End Sub

Friend Sub SetTabStopsAccordingly()
    ' Call this in the form activate event.
    ' After this first call, it will automatically be called when the tabs change.
    Dim ctl As Control
    Dim ctlTheControlOrContainer As Control
    Dim ItsOnTheTabControl As Boolean
    Dim ptr As Long
    '
    For ptr = 0 To frm.Controls.Count - 1
        Set ctl = frm.Controls(ptr)
        Set ctlTheControlOrContainer = ctl ' The control might be on a container that's on the SSTab, rather than directly on the SSTab.
        Do
            Select Case True
            Case TypeOf ctlTheControlOrContainer.Container Is SSTab
                ItsOnTheTabControl = True
                Exit Do ' The way out.
            Case TypeOf ctlTheControlOrContainer.Container Is Form
                ItsOnTheTabControl = False
                Exit Do ' The way out.
            End Select
            Set ctlTheControlOrContainer = ctlTheControlOrContainer.Container ' Must deal with controls nested deeper than the SSTab control.
        Loop
        If ItsOnTheTabControl Then
            ' Not all controls have TabStop property, so we must set error trapping.
            On Error Resume Next
            If ctlTheControlOrContainer.Left >= 0 Then
                ctl.TabStop = TabStops(ptr) ' If it's showing, restore the original TabStop value.
                ' Must also fix the problem with combo boxes having an internal focus set.
                ctl.SelStart = 0
                ctl.SelLength = 0
            Else
                ctl.TabStop = False
            End If
            On Error GoTo 0
        End If
    Next ptr
End Sub

Private Sub tabCtl_Click(PreviousTab As Integer)
    SetTabStopsAccordingly
End Sub

Private Sub tabCtl_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
    ' This allows other controls to close up when user click off.
    ' The problem is that clicking into the body of the tab control does NOT cause change in focus.
    ' The control with the focus keeps it, and it may not close up as typically happens when clicking on dead space of a form.
    ' You may also want to consider placing this "SetFocus" code on the labels on the tabs.  This is NOT automatically done
    ' because the programmer may want to use a label click for other purposes.
    tabCtl.SetFocus
End Sub
Usage is quite simple. Let's say the above class module is named clsFixTabControl. Let's further say that you have an SSTab control on your form named tabExamData. Under these conditions, all you'd need to do is the following in your form:

Code:
Option Explicit
'
Dim FixTabControl As New clsFixTabControl
'
Private Sub Form_Load()
    SubClassForFixedSize Me ' This is to accomodate the Tablet PC.

    ' possibly other code.
End Sub

Private Sub Form_Activate()
    FixTabControl.SetTabStopsAccordingly

    ' possibly other code.
End Sub
And that's it. Your tabstops will now work perfectly on your SSTab control.