Despite the risks, you shouldn't let the fear of theft stand in your way of owning a good bike. If we all tried to avoid risks all the time, we'd never leave the house. You may well be walking and get mugged, let alone bike crime. It's your right to have a quality bike of your own choosing. I think it's sensible to use this only for decent rides, when you'll either be on it or have it in your sight at all times, and have a basic bike for dicking around on, going to the shops, pub etc. If you ride your good bike in this way, less often, you'll look forward to it more too.
Despite the risks, you shouldn't let the fear of theft stand in your way of owning a good bike. If we all tried to avoid risks all the time, we'd never leave the house. You may well be walking and get mugged, let alone bike crime. It's your right to have a quality bike of your own choosing. I think it's sensible to use this only for decent rides, when you'll either be on it or have it in your sight at all times, and have a basic bike for dicking around on, going to the shops, pub etc. If you ride your good bike in this way, less often, you'll look forward to it more too.