Finger joints will make your corners stronger, definitely.. but I must pose the question.. HOW STRONG do the corners need to be?
Is it worth the TIME to make those joints?
Is it worth the cost of the Dado blade?
Is it worth the extra effort to seal those corners and joints?
Making the jig isnt too hard. i made one, made quite a few boxes with it.. by the second year they were splitting and warping, normally from the corner of a recess. I still have and use a few of those boxes, but I have to stay on top of them more than I do the rabbit joints or butt joints.
I switched to rabbiting the edges, and that made a difference in the splitting and warping until it was pointed out to me.. that I would be replacing them in five or so years, give or take a couple anyhow...
The philosophy I walked away with is that woodenware is disposable. In other words...
Make it GOOD, EASILY.
I have been building butt joints, and have had some pretty surprised people using them.. No splitting, separating etc.. the corners are easy to seal and keep sealed. I use glue and BRAD nails. The boxes are strong enough that i can stand my fat *#$ on the CORNER endwise without it giving up. I would imagine if I bounced on it it would break, but then I can probably break the other joints too..
I have boxes inherited from my mentor that are close to eight years old. butt joints, and they are still doing fine. I also have already replaced most of the box joints I built.
The difference may be in the details, what paint you use etc... I use the cheapest exterior paint I can find.. once its chipped off the corners it doesnt matter how expensive it was.. Maybe I am not sealing the box joints well enough, they need more than two coats of paint.... it remains, the butt joints dont, they seem happy with cheap paint, and the bees havent complained yet, despite being female. (oops, did I say that?)
It is ESSENTIAL, that you build them like you want!! I am just pointing out something that made life a LOT easier for me.
I dont try to build fortresses anymore. I sell quite a few, and have no complaints. I have lost sales because they are not box joints, and I have lost sales because the hand holds are routed and not undercut like commercial hives.. I am OK with that.. I build them for MY use. Selling a few is just a bonus.