BikeFreak,
Your're asking your questions as if you walked into your local locksmith shop and asked a locksmith who carries all these things and can just open a catalog and tell you. Most of us here are hobby lock pickers, some of us are lock collectors, and half a dozen are actual working locksmiths from several countries. Nobody off hand knows if a certain Abloy Protec cylinder will fit into a certain Viro padlock or chain you found, this would require some research and our time.
You said you had an expensive bike, like what a $1000 bike or like a $5000 carbon fiber frame? And what are you protecting from? Bad guys on streets of NYC or SF while your bike is outside for 4 hours or do you just want to lock it up in front of a coffee shop on Sunday morning in your affluent suburbs? Those details will help us or anyone you go to, offer you the correct level of security.
Please also search the forum for past bike lock threads, you may find some good recommendations there. When I pull off the bike path to stop at a store for 15 mins I use an Abus 10mm 6 foot long cable and a Medeco shrouded padlock, probably wouldnt leave it overnight with that cable but better than nothing if just running in somewhere.
Squelchtone