Good advice already given here. Personally, I like it. It gives me a little more precision on distance control when the desired distance is between avatar movements. I follow my putting stats pretty closely, and while I have also changed putters, I believe Putter Pal is the biggest factor in the small improvement in my stats since I started using it. My 1-putt percentage has gone from about 46.8% to about 47% and my 3-putt % has gone from about 4% to about 3.9%. That's a small difference, but I'm not a great putter to begin with so I'll take anything I can get.
That said, there is apparently nothing on God's green earth that will help me get the read and speed right on 4-footers at Oakmont. :)