My first QWERTY slider was the Samsung Sidekick 4G, which also had the angled screen. I still have it as an alternate phone, even though the OS is so old I can't update anything any more. But it accepts full-size SD cards, which was useful for the data SIM I bought for use in Japan so I could use it as a hotspot.
My current QWERTY slider is the LG Optimus F3Q. It's not as nice as the Samsung, but has LTE support that the Samsung doesn't. It's getting a bit long in the tooth, though, and I'm really looking forward to replacing it with the Pro1.