I have a one that I did the mod on, I plan on getting two more of the Sure Flow models, they work great, at least the one I have now does, occasionally I have to turn off and on(I turn some pumps off during water changes) a couple of times to get it to go in the right direction. I think the new Sure Flow mod eliminates this problem. I would use the 900's, from now on to do the mod, I don't think you are sacrificing much flow, the reason for the stronger electrical draw on the MJ 1000 and MJ1200's is to push the 60" head and handle the back pressure of the little hang-on skimmers that use them, IMO. You are only dropping 65gph on a stock 900 at 8wt, compared to a 1200 at 20wt. Also, have been told that if you put a 1200 impeller in a 900 it becomes a 1200
. So, by making them stream pumps you no longer need the extra push, as you would in other applications. Just my 2 cents.
Matt