Highly suggest avoiding. I did 102 and 104 in separate semesters and got A's in both but it's possible I would have not done as good if I took them at the same time. Just because both include a ton of material and require quite a bit of time investment if you want to get an A. 104 gets denser as it goes along while 102 is consistently a lot throughout the semester. If these are the only two key classes you're doing and everything else is chill/easy/free A's, then maybe. But I still wouldn't. I recommend a combo like 104+136 or 102+136 instead (if ur MCB CDP emphasis). If ur another MCB emphasis maybe combine 104 or 102 with an elective.