The advantages of the mini locks are that they are lighter, and there is less room for someone to get something in there, like a bottle jack, for prying attacks. The disadvantage is fewer locking options. At least as I see it.

The less room that is left over inside the shackle of the lock, after the bike is locked up by whatever method you choose, the more secure it will be. Of course, if they want to cut it with an angle grinder, none of this matters. This refers to prying attacks only. I guess it might apply somewhat to a hacksaw, as there is less room to work, but whatever.

There are different lengths of mini locks also. The mini generally refers to the width of the crossbar. Usually about 3.5" for a mini, I think. I recently got a mini with a 7 inch shackle, and so far, with admittedly limited use, I'm liking it. I keep seeing things that I can lock to, that my original mini (smaller shackle) would not work on. I do use an OnGuard Bulldog Mini (my original mini) on my old mountain bike, and it works great. I just have to find things I can lock to, and put the bike right up against them.

What you have should work, but it might be tougher to find secure things to lock to.