S7-200 and 1200. OPC server platinum thread.

[vishnu-krishna]

Hi! Im newbie in PLC.
Currently i have s7-200 cpu + cp243-1 and s7-1200 cpu connected to factory network (ethernet). The goal is to trasnfer data to oracle database from these two cpus. My part of work is to convey data to the opc server. Now im considering 3 variants:

-Pc access OPC (6ES7840-2CC01-0YX0). Really cheap, but i ve noticed that there is "SINGLE LICENSE F.1 INSTALLATION". I wonder what does it mean? It means that ill be able to install it on one machine for multiple times or just one time? Also, as far as i can see on the web, there could be some issues when working with S7-1200 because it was originaly designed to work with s7-200.

-Simatic Net OPC. What are the advantages of this one?

-Matrikon Siemens S7 PLC OPC Server. Seems a good one, but expensive.

I need to transfer only about 30 tags and that keeps me from spending money on Matrikon and in this case my priority is Pc access, but some says that it can be unstable sometimes.
BTW i have a WinCC 6 (not flexible) installed on some computers in a factory network. As far as i know WinCC 6 includes its own opc server, so is it possible to transfer tags there?
Is there any description of how should i configure S7-200 in Microwin to connect with OPC/WinCC 6?
Thanks for considering my request!