As far as the TC Dirk goes, this may not be a good example for your first TC strap. If you check out my review I mention that the strap is somewhat stiff and feels nearly indestructible. But that's the point - it's a waterproof strap. If you try out other TC straps you'll see there's a wide variety of hides and most are designed to be very supple.
BTW, I took my Dirk, soaked it in Neatsfoot oil and then wore it for a day - it definitely softened and loosened way up.
As to your looking for an MP4, there have been 2 or 3 recently for sale on the Paneristi Boards. I bought one - great strap.
Dave