Question regarding speed on WD3200AZDX

I was looking for a 320GB upgrade for my computer (custom built). I am currently using a WD1600AAJS - 160GB SATA hard drive. I came across this one:

Western Digital WD3200AZDX - 320 GB IntelliPower 32 MB Cache SATA 6 Gb/s 3.5" Caviar Green Hard Drive

The part has great specs, it’s right in my budget and they have plenty in stock (I called to confirm)… My question is regarding speed. This drive provides plenty of space (double what I have now), but how much of a difference in speed would this drive make? Does the 32MB play any role in terms of speed? I would like a hard drive that is larger in capacity and faster in speed. Is this an upgrade that would be recommended? Thanks

Caviar Green drives spin at 5400 RPM. Your WD1600AAJS spins at 7200 RPM. However, the WD3200AZDX has a greater data density (GB per platter) so its throughput would be significantly faster.

The spec sheet specifies a maximum sustained data transfer rate of 150MB/s for the WD3200AZDX:

One thing to be aware of is that the WD3200AZDX is an Advanced Format model. This means that you will need to align the partitions if you are using a legacy OS such as Windows XP.

Model Number Format for WD Products - Western Digital: