asp.net mvc - Providing synchronous behaviour in CQRS when needed? -

i using asp.net mvc nservicebus , vast majority of commands can executed eventual consistency in mind, there small minority of tasks immediate consistency appear simplify things.

i have done plenty of research on various methods used accomplish few come kind of justification why particular method preferable. don't have experience nsb in production environment, nice know if methods limit scalability in way.

the following broadly methods have come across: -

• no synchronisation, fake information client. reservations 1 firstly, have deal case have faked data , command has failed (unlikely scenario) , more importantly, if initialisation of data within command complex, ability fake data not feasible anyway.
• reply (or publish event recieved client) when task completed. reservation 1 means distributed architecture becomes more complex , not sure if load balanced clients cause issues 1 of client machines should recieving reply.
• poll read store until data present. reservation 1 puts read store under more load other options.

are there options better above 3 , if so, why? if not, of above 3 better , why?

i assuming answer not subjective , 1 suits using nservicebus implement command infrastructure in cqrs better others.

thanks.

my take on actual endpoint should not performing work handing off 'task' (application service / operation script) object. that object performing work immediately.

so cases absolutely have have 100% consistency rather call same task object rather sending command later processing. may still want command other scenarios.