They are long roi'd and are probably almost at 100% return after break even.
But sometime, you just gotta shut them off. For most of 2015 the return per GPU was 20-25cents per, per day. For the electricity they consumed, it would have been more efficient to run S3's or even S1s.
So GPUs are really a exclusive thing. You need to either have a miner/kernel that let you mine at high speed than others. Or you just get the good stuff when they come up and then let them rest or sell them.
I ROIed on all of my GPU's aswell. But I choose to sell them and go into asics. Just for me I thought was best bet.
I did not get the crazy pricing GPUs had during height. But I got a good amount still for my 270/280's. Kept very few of them as it was great profit selling ontop of ROI. So was pretty amazing mining back then.
Well a bit over one month ago, i had people offering me 125$-150$ per GPU, In the end since then i made about that much per GPU with Ethereum, before the price crashed. The reason i ended up not selling was quite a few was acting all scammy and stuff. (Rest was price way too low) And also the hassle of packaging the whole rig back into pieces.
It was only for a short while but it made me wonder if i shouldn't just keep it handy since all in all 15$US per day for 1150W was pretty good. Now its 5$~ per day, its about the efficiency of S5's. Its not yet back to the usual 1.5$ per day from X11~ 2 months ago.