That “pocket head” is also known as a Robertson head in Canada (and in the USA) where it’s almost a standard screw head. I’ve seen a of furniture held together using screws with that head.
Axminster do a good range of torx pocket hole screws. They're partially threaded which may / may not be a good thing based on your intended application.
The core of MDF is very soft. I would imagine standard ' bugle head ' screws would be more secure assuming you had used a countersink bit. I love the Robertson head screws but they are hard to get this side of the pond.