Depends
The Pro is better for spin than the other two. 16 mains offers more spin than 18 mains if they're the same headsize. I'd totally buy the Pro, but that's just me. You should really demo them first though. You don't seem too experienced in choosing one without trying it.
The more open pattern offers more spin. The more dense pattern offers better control. The 16 x 19 should suit your needs just fine.
If you are a very good player say 4.5 or higher then go with the Pro.
http://www.tennis-warehouse.com/descpage...
If you are so so or intermediate then perhaps you should try the Pro since I don't like 18 x 20 frames and won't suggest you buy them. But then it could be just me since I like to string high which makes a dense frame feel like a board and does not allow it to give much so reduces power as well.
Have you considered the Head MicroGEL Extreme Pro Racquet. If you can get used to the funky yellow color it is a nice frame.
BB ALU Rough 16 is the best for spin although Head RIP Control 16 isn't bad either and cheaper.