Hi,
I've been in the very same situation since I purchased my scope a few years ago. My original decision was to have a MIXEDsignal oscilloscope, to analyze the correlation (both on time domain and transferred data) between the analog channel(s) and different serial protocols (mostly i2c, SPI, and UART).
Within the past years, I've been agonizing during nearly EVERY measurement session made with this, otherwise rather capable scope. MSO version is a joke... There was only one and only use I found it as a good tool when I tried to find the main cause of a serious sync issue in an array of shift registers (595s). At that time, I needed way over 4 channels to be synced.
For any future buyers, please note, AVOID any software-based decoding functionality in any scope. Most of them are barely capable to meet your requirements.