The default angles on Jake’s grips depend on the model. If you would go for a “I AM. Recurve” grip (others being the Barebow and Lowered Pivot versions), the default angle is at 38 degrees making it a Mid.
Compared to the Low WNS grip and most generic stock grips, it certainly gives a much more defined lifeline and a flatter pressure area. This will help with shot alignment and it comes (optionally) with a small rhomboidal shape with small antislip, just on the pressure point (about 2cm below the real pivot point of the grip). This “Border pressure point” will give you positive feedback when setting up and drawing.
The Master, on the other hand, promotes the “pointing with the thumb” shooting (like Brady does) and comes with a default slant on the pressure area. The lifeline edge is also defined and bulges a little. You can feel that small bulge in that pleasurable point at the center of your palm. And if you add a lifeline ridge on the options, that 0.7mm protrusion will “click” in your lifeline when you set up your position, while it will disappear when at full draw