On average, the JB (BB-SE) series is quite a bit more expensive than any other competing models from Maxtor / Seagate. The 80GB Model will cost you around £110 at the time of writing this, which is around £40 more than a 80GB from Maxtor / Seagate who only ship drives with 2MB buffers. The 120GB model will cost around £160-180 depending on where you shop.
Earlier I mentioned the selling point of these drives - the 8MB buffer that they are equipped with. Let me explain a little -
The buffer (cache) on a HDD has the job of guessing which data is going to be requested from the disc. The data is then read, and loaded into the cache. Hopefully the HDD will get things right, and when as predicted your computer requests the data that the HDD has guessed at and loaded into the cache memory, it can be sent ultra fast to your CPU or memory. Obviously the cache memory is much faster than manually reading the disc, and this is the advantage of using cache memory. The more data that can be put into the cache, the better performance you are going to get from your HDD.
Coupled with the 8MB cache memory, the algorithms that WD have used are very detailed. The algorithms are what predict which data is going to be requested, so therefore the more 'clever' your HDD is at guessing which data is going to be needed, the more efficient and useful the cache on your HDD becomes.
So, are these drives worth the extra? Or are they just a fuss over fancy figures and model names?