[JERRY2KONE]

There are very little subtle differences, but they all last about the same. Spring steel compared to hardened steel is just a bit softer. So instead of rounding your screws you will round the tools faster. I use hardened steel tipped tools with grade 12.9 steel screws and have very little problems. No matter what you use if you over tighten things you will destroy either the screws, the tools, or both. The only real benefit from one tool over another is the feel of the tool in your hand. Just keep a good supply of tips in your toolbox and treat your tools accordingly. As the tips get worn down just grind the tip length down a little bit revealing unused edges. Avoid using ball type allen tools unless it is a screw that is impossible to get to otherwise. I rarely use the ball type at all anymore. I have tools from several different manufacturers in the USA, Europe, and Asia and they all have their pros and cons, but they all do their job if treated properly.