I would probably up a grade if you are doing an RV12, there are a lot of rivets to pull and the cheaper guns need constant fiddling and clearing. Ask us how we know.....
I would at least go up to Northern Tools - better Chinese carp
Once you have it, pay attention to filling instructions, you may also consider taking the smallest die and drilling it out to match the LP4-3 mandrel size so it is a nice snug fit. Then polish the nose of the die on a unitized wheel or similar so it is nice and smooth - it makes a difference to the finish on the head.
It may take a while to 'break in' - it may jam a bit, don't bother with the catcher at the back - useless. Be prepared to take a while getting it set up and then it will be trouble free. A squirt of WD40 down the nozzle ever other week helps as well.
The last thing you want, when faced with a loaded wing or fuselage is a sticky gun