Well first thing to suggest is that you get your pvm first, if you haven't yet? - Sounds like you have but just checking.
Some have different rgb setups. I think a few even had a scart...
That being said; I believe rgbs via 4 bnc connectors was the most common solution. Simply because scart only came along relatively late in the day for the euro zone.
Back in the day BNC connections were common and straight forward ways to connect [and lock in] specific lines. The scart cable has lots of pins designed for various functions; however for your purposes the adapter simply takes 4 of them - the r,g,b,s for the picture. By comparision other connectors can be brittle, easily dislodged and hard to troubleshoot [think working in a big studio etc].
As mentioned an audio break out if also useful to to then pipe into your pvm[if possible]/stereo/headphones/speakers.
You can readily get hold of BNC <-> standard phono plug adapters for each plug... probably for cents/pence - meaning you can always use this to quite easily connect the rgbs signal to nearly any equipment that wants an rgbs signal - recording equipment/scalers/arcade monitor etc.
Personally for my various setups I use this little device to save me the labour/mess of chopping up a scart cable. Not sure how easy to find an rgbs version is elsewhere [beware not the same as some other 4 output scart adapters which basically connect different pins]:
http://www.tvcables.co.uk/cgi-bin/tvcab ... APTER.html
note with the above type adapter, you'd want a female<->female adapter and you'd need to break out the audio some way yourself...
