Sony AC Adapter confusion

My wife just got her new SVS13 laptop and now wants an extra power adapter. The one she got with the laptop was the VGP-19V38 which she likes because it is relatively small. This is rated at about 75W. The plug diameters are 6.0/4.4mm. For home use, we don't mind one slightly bigger; such as a 90W unit. I cannot find this exact model on the Sony Store and even if I could, it would be overpriced.

In trying to find a replacement, I see MANY that are supposedly compatible...but there are just SO many. Why do all these exist if they all output 19.5V and supply 75-90W. Some of the models I have seen as compatible are: VGP-19V30, 31, 32, 33, 34, 35, 36, 37, 39, 41, 43, 48, 49, and maybe more. She definitely wants a right-angle plug. Does anyone know the differences in all of these models?

 

Try the iGo green range - here's the store link. Laptops - Power at iGo, Inc.. Yes it's an US website but they seem to deliver internationally.

They do a range of shapes and sizes. Give them a try. (I assume all sony vaio power jacks are the same [someone correct me on this] and well Sony hasn't appeared to have changed the power jack connection.

I feel that they're reasonably priced as adaptors go, cheap power adaptors from ebay .etc can be dangerous and cause fires.

Well specs you should look for aren't just wattage, you need to look at the voltage and amps the laptop needs.

I believe the sony s series is 19.5v @ 4.7 amps, so look for an adaptor that matches this.

Note you get what you pay for these days, and if it too good to be true it probably is.