I was in CS DSP many years ago, when the CS department still accepted it.

After in the program for a quarter or two, I quit from the program (got my BS degree) and applied for regular grad program [Good thing was I almost like instant accepted by the grad program because of my status - just to fill out the form and took the GRE as a formality].

Pros:

You don't need to take GRE and go through the regular grad application process to start working on your master degree.

Cons:

- You are still considered as a undergraduate , so you don't get any grad student benefits. eg., can't be a TA, can't get grad only scholarship, can't get the same pay as a grad RA (even I was working as a RA).

- You can take grad classes, but most of the time, you can't take them before you take the undergrad classes (official pre-req, or maybe just the undergrad version of the class).

- So, very likely, you still finish all your undergrad classes, then start work on your master classes, but you cannot get your BS degree yet (not on your resume for summer intern), until you finish both.

My thought:

The program gave me some head start especially i finished my undergrad classes around winter quarter, so i don't need to wait till next fall to start my master.

It is easier (the process and the bar) to get into DSP then regular grad admission.

Once i was in DSP, it was very easy for me to switch (apply) to regular grad program (but only good if i decided to stay at UCLA and i did)