Missy,
although i have nt started to use the Avent DUO, but i should think tt if u are fine with the manual, and is suitable, then the DUO is prob a bonus to u. Reason why i got my DUO is also becos i liked my manual. But cos i have very low SS for my 1st child, I m determine to invest in this pump to boost my ss and also to save time for my 2nd child. I used to spend abt 30-40min to pump a miserablee amt of BM for my son. Aft tt i got a medela plus, was noisy and didnt up my ss. But DUO wasnt available back then in 2004. the cons of the Avent manual was the tiring part esp for me who only give my son EBM and not latch.
I also tried the demo set at Robinson, the pump was almost silent and easy to assemble.
But heard a few comments regarding the weight of the pump. If u intend to express in ur workplace, might need to consider placing it in the office instead of bringing it home everyday unless u drive. For me nt an issue as i am WFHM, if i go out prob will jus bring my manual pump.
This is jus my tots, hope mummies who have reeally used the AVent DUO can help us by giving more comments!