it is easy to cut the retaining strap on a Grohmann (I have a #4) if you are not really careful... my only minor criticism  
I've spent a little bit of time looking at the 
#4 Survival knife and there are sheath options out there without the strap. I've seen them sold with pouch sheaths, both those 
with and 
without a sharpening steel holder. It looks like the sheaths can be 
bought seperately as well. 
Of course there is also the option of getting a custom sheath from a 
Canadian sheath maker. I found some pics of this set-up 
here.