Congrats on the forthcoming nuptials!
I'll admit, I don't know anything about any of those bikes, other than I wasn't thrilled with Tiagra when I had it 6 or 8 years ago. Could be different now.
I recently made the decision to commute entirely by bicycle and transit. I live in Tacoma, work in Kent, and downtown Seattle. My girlfriend and I share a vehicle. Because I have two functioning legs and a bike to ride, i see no point in having my car sit at the park & ride 10 hours a day waiting for something bad to happen to it. Since I started commuting via transit I have become uncomfortable riding in cars on the freeway (maniacs in cagers), especially during rush hour. Plus a bus pass is ~$100/month. No need for gas, insurance, tow trucks... Or at least a little less of each. Actually, my employer pays for my bus pass and I'm trying to make it a company wide thing.
I don't know where you live, or how far you are from work, but my commute only takes about an extra half hour. The time i used to spend getting bent out of shape sitting in traffic I now spend napping, browsing craigslist for bikes/parts, reading forums, and watching weird people on the bus, etc.
We've made the one car thing work for a few months now and I don't see it changing for a while and we're expecting a baby girl in May.
Give it a shot. Your friends will envy you.