Value
For the materials used, construction and overall weight, this knife is way underpriced. Other folding knives of this caliber could cost up to $100 more and other folding knives at this price can weigh twice as much. This knife is a steal.

Overall Construction/Materials
The Build
The knife is comprised of a metal frame housed inside an injection molded resin handle. This helps keep the weight down, and the durability up. Everything is held together with torx screws and utilizes an oversized, adjustable, pivot pin for easy operation.  

The Lock
The blade locks in place utilizing Benchmade’s own Axis Lock Technology, which is comprised of a spring-loaded steel bar that seats itself into a notch in the blade. It is almost impossible to disengage without intent.

The Steel
X15-TN stainless steel is also used to make scalpels, which require a precision edge for cutting.  It has a Rockwell of 56-58, and though it does dull more frequently than other metals in its league, it can be sharpened with ease. This metal exceeds any expectations I would have for a pocketknife.

Durability
Because of its lightweight construction, someone just picking this knife up—without really using it—might pass it up for something that feels a little more significant. But, don’t be fooled, the construction of this knife is second to none. The two drawbacks would be in the finish of the blade and the material of the handle—both can get scratched up pretty easily.

Design/Ease of Use
If having a pivot pin that allowed you to adjust the tension of the knife blade wasn’t enough, the 551H20 can be opened with one hand. With a flick of the wrist, the knife blade can swing open and lock into place. Also, the lock can be disengaged from either side of the handle and is spring tensioned so it cannot slip out of place.

The drop-point design of the blade is popular with hunters and is also great for general cutting and slicing. This particular model has a serrated blade, which is an added benefit when cutting rope, and other woven or braided materials.

Edge Retention
The one thing we all know about scalpels is that they can be sharper than a razor, but the one thing you may not know is that scalpels require more frequent sharpening. In my mind, this is a small price to pay when you have a material that can cut into almost anything and rarely needs a good cleaning.

Upkeep
Benchmade uses torx screws on many, if not all of their folding knives. This may prove to be a little inconvenient to the average user, who may not have the exact torx bits with them on their adventures. But, for an additional $20, you can pick up the “Bluebox Service Kit” from Benchmade, which contains all of the tools necessary to maintain this knife in the field.