Since my PC has crapped out, I was looking at getting a new Flex polisher. I was looking at either the XC 3401 or the L 3403. I noticed that L 3403 is a bit lighter which is nice b/c using my PC would become very tiresome when doing a 4-hour job. Also, the 3403 is less expensive. Are there any major differences between the two? Is one generally better than the other performance wise?