Yes, the accumulator is designed to keep liquid from the compressor. It also contains the desiccant, a substance that removes water vapor. In a system that contains a receiver drier, the receiver drier contains the desiccant. While both systems should be operating with an efficient condenser and have nothing but liquid refrigerant from that point on, that's not always the case. Orifice tubes can handle bubbly refrigerant better than expansion valves, so they pass on the receiver drier and go the accumulator route. The expansion valve systems tend to stick with the receiver driers to allow for an uniform liquid feed to the expansion valve.

Is one system better than the other? Hard to say. In good condition both cool well enough. I suppose an expansion valve is an extra mechanical part to break and/or leak, but I don't see it often. Sometimes an expansion valve will make noise at a particular RPM or load, but it's rare. Some systems, particularly the dual systems used in vans and Suburbans will have an orifice tube feeding the front evaporator, and an expansion valve for the rear.

To further complicate things, many vehicles have variable orifice tubes, and now many compressors are variable displacement as well.

What's best? Beats me, they all have ups and downs. Personally, I drive with the windows down and the A/C off...

MV