I don't think it's really that bad, I'm running it inside a VM with 4GB RAM, and it's still have ok performance. My host machine is a 3 year old computer with i7 2600k CPU and 8GB RAM.
Mine is a 1.5 year computer with i5 cpu and 4GB RAM. Sometimes it will fail to start with no response. After start i have to wait long hours to download the useless blocks (old blocks is useless for me). And i tried twice, but just failed to finish download the block and the client can't be opened correctly.
This sounds a long complaint, but it is real, and i am trying the third time, downloading...