Need new interface, which one?

I apologize in advance as this has probably been beaten to death but could really use some advice. I originally used just vst’s but now Im using mainly hardware and really noticing my current setup is garbage. I started producing with cubase a few years ago then moved to logic cause I brought a mac and figured that was the way to go. Well, I was wrong! I hated it and now Im back, got 6.5 a few months ago and just bought 7 and I love it! Such a huge update. Anyways, Im looking at a new interface and thought may as well get one thats integrated with cubase. First off, I produce electronic music so i just need something for my external synths. I have 3 synths right now and am using a m-audio fast track pro with a piece of poop mixer and midi goes through the interface and my midi controller. I know the steinberg don’t have midi, which kinda sucks, but which one is my best option? Is the MR816 CSX overkill? Also, is the only difference between the ur and the mr series the usb vs firewire? Thanks in advance

MR816 might not be ideal if you’re only using synths as inputs, as that’s all line level while the MR816 inputs all have preamps. It works fine, but you can’t bypass the preamps so they’ll leave a mark on your signal. If that’s positive or negative I don’t know, depends on your taste I guess.

There’s a bunch of differences between the UR and MR. The UR comes with more software (channelstrips you can use in Cubase iirc), and the MR can be daisychained which the UR cannot.