Patern parts or 2nd hand OEM??

I'm new to the world of classic car ownership so really I'd like to see what the pros are thinking..
I understand the importance of OEM panels and the better quality fitting and materials usedand when it gets re sprayed its all the same colour anyway. but I'm finding some engine components are start to give up.
 I was wandering if there was any benifit to searching high and low for a 2nd hand OEM part that could well have done a 100k+ than nipping down GSF and picking up a brand new pattern part?

Thanks guys. 

Depends really, no point buying an oem part if its possibly worn out, i think its also about being sensible, a set of new pattern pistons for £10 are probably not of the highest quality.

Agreed, always stick with 2nd hand OEM over pattern parts, unless its something that is clearly worn out… 

+1 try and get the best OEM stuff you can.

depends on the parts really. running gear, ignition etc parts are fine as long as you buy good quality gear. certain electrical sensors such as ecu temp, oil pressure etc you'll want new oem. when it comes to panels and trim, oem is always best pattern stuff is just never going to be as good

What you should also note is some 'pattern' parts are actually made by the original component manufacturer, just not supplied through VW, and in some cases, are actually better than OEM.