They make good remotes with the exception of the 880, but I really wish they would give up on their own proprietary batteries. My old 680 works great for 4-8 weeks on a set of four AAA eneloops. My Harmony One can barely last a day or two with barely any use at all. Sure, its nice to include a fancy charger/cradle, but not when the included battery is terrible. A Harmony One that doesn't come with a charger but takes AAA's would be a very good remote.
They make good remotes with the exception of the 880, but I really wish they would give up on their own proprietary batteries. My old 680 works great for 4-8 weeks on a set of four AAA eneloops. My Harmony One can barely last a day or two with barely any use at all. Sure, its nice to include a fancy charger/cradle, but not when the included battery is terrible. A Harmony One that doesn't come with a charger but takes AAA's would be a very good remote.
My 880 lasts weeks on a full charge. That said, the contacts on the volume up and channel up are starting to go on mine (have had it for about 3 years now). Don't know why you don't like the 880 Binky. To me it was the best combination of LCD, number of devices, very good IR strength, and physical buttons out of all the Harmony remotes. The touch screen ones suck to be honest, since you have to look at the remote and stop looking at the movie/show to do anything that uses the touch screen since the is no tactile feedback to allow you to have confidence that you touched in the right spot.
Out of the current ones, the "300i" just doesn't allow enough devices, even for a bedroom build, 4 devices is pretty restrictive. The 650 Advanced is just way over-priced for only being able to handle 6 devices. Heck, my parents have over 6 devices in their living room that they need to control for it to all work with one remote! The 900's aren't bad, but again, the touchscreen really limits it compared to the older 880 where you could have 8 functions on the LCD screen per screen. I mean, to me, they have really gone back in quality/functionality since the 880/890. The biggest gripe with the 880/890 is that the buttons eventually wear and requires you to open it up, clean out the contacts and re-apply the contact paste to them.
Debating whether to get one of these or just go all the way to a RedEye and control via smartphones/tablets.
I don't get the 5 and 6 device limits - especially having to 'upgrade' to get 6 devices (why isn't it 26?). 6 isn't even really enough if you throw in a couple of video game consoles or a laptop or some such thing.
The 520 does 12 devices, and it was the cheapest one they had at the time. Makes no sense to me...