You will find the quality of the eastern trading vac is not as good as the dual pump type one. We have both types. The eastern tradding type (which is also the same as the Kiam etc..) has no problem with power however on on one job the pole got blocked and the drum was sucked flat in on itself so we had to beat it out and strengthen it with metal bands.
The eastern trading/ omnipole type which is made by soteco is the best value for money when it comes to quality, even so the trolley is flimsey and the origional inlet is not up to the job.