Siebel java data bean, Inbound web service and queue based transport

Hello experts,

As integration solution for heavy incoming requests which of the below approaches a designer should prefer in sequence.

1. Siebel Java data bean(calling siebel object manager using java code)

2. Inbound Web Service

3. Queue based Transport

Suppose I have around 10000+ near to real time incoming requests to be processed per hour in siebel which of the above approaches will work for me. I assume queue based approach will be a better solution but can other approaches too manage this much or more heavy load?

Thanks,

Suresh