IWB
As a long time carrier using IWB holsters, I can honestly say that I prefer any other method of carry. I never bought bigger pants, just un-notched my belt a bit - but - there is considerable pain in your lower back and butt cheeks that develops when sitting in a car seat or anywhere else, for extended periods, when carrying in this manner. Also, it is very slow to access your firearm from this position, although it is probably the best of all concealed positions. The small of the back IWB (I'm assuming this is what you are talking about, if not, please forgive me) is good for a back up weapon. I've found that putting smaller pieces directly in my right rear back pocket (I wear jeans about 95% of the time) with a handkerchief on the outside to cover print through and a shirt or jacket over the belt - is the most comfortable. When I'm carrying a larger piece I generally strap it on the strong side or carry cross draw with a shirt or jacket over.