Attempt at extending example further

Program.cs

static void Main(string[] args)
{
    var browser = new ServiceBrowser();

    var observableFound =
        Observable.FromEventPattern<ServiceFoundEventArgs>(
            h => browser.ServiceFound += h,
            h => browser.ServiceFound -= h)
        .Select(e => e.EventArgs.Service);

    var observableError =
        Observable.FromEventPattern<ServiceSearchErrorEventArgs>(
            h => browser.ServiceError += h,
            h => browser.ServiceError -= h);

    var observableFoundWithError = observableFound
        .Materialize()
        .Merge(
            observableError
                .Materialize()
                .Select(x => Notification.CreateOnError<Service>(new Exception("Error"))))
        .Dematerialize()
        .Synchronize();

    var subject = new Subject<Service>();

    var sub = observableFoundWithError.Subscribe(s =>
    {
        var observableResolved = Observable.FromEventPattern<EventArgs>(
            h => s.AddressResolved += h,
            h => s.AddressResolved -= h);

        var observableResolveError = Observable.FromEventPattern<EventArgs>(
            h => s.ErrorResolvingAddress += h,
            h => s.ErrorResolvingAddress -= h);

        var observableResolvedWithError = observableResolved
            .Materialize()
            .Merge(
                observableResolveError
                .Do(e => Console.WriteLine($"Error resolving: {s.Name}"))
                .Materialize()
                .Select(x => Notification.CreateOnError<EventPattern<EventArgs>>(new Exception($"Error resolving address for service: {s.Name}"))))
            .Dematerialize()
            .Synchronize();

        var resolveSub = observableResolved.Subscribe(
            r => subject.OnNext(s), 
            ex => subject.OnError(ex),
            () => Console.WriteLine("Resolve Completed"));

        s.ResolveAddress();
    });

    using (subject.Subscribe(
            s => Console.WriteLine($"Found and resolved service: {s.Name} ({s.Address})"),
            ex => Console.WriteLine($"Found error: {ex.Message}"),
            () => Console.WriteLine("Found Completed")))
    {
        browser.Search();
        Console.ReadLine();
    }
}