Aqua-c ev180 or Others ?

[TVR]

Hi:
I have this skimmer setup and running in my system.
Let say, my system is about 180G total (Main+Sump) water volume only.
This skimmer rated for upto 180G and I am using it as insump with Rio 3100
*A guy from lfs had come to my house to estimate the price for a new system setup and then had a look at my system and recommended me that this skimmer is not good and I should need to change and use the one look like the tower, I think he meant something like RedSea or the PM ...?
My Aqua C 180 is doing great for me so far with lots, I mean LOTS of collected waste that my uncle helped me setup to have a collection cup drained to 5G containers.
My question is: Since I am new and still under learning curve, I am confused and dont know is it right that skimmers do perform differently for each brandname / design or should they be under the same principle as I thought and that the differences were only the designs and the compact / conveniences each gave and the prices of cause ? SHOULD I UPGRADE MY SKIMMING AS HE SAID ?
Because: I do heard the rumorsthat dont always listen to the experts at LPS (those like PetLand, PetSmart... not our reef store though ) - I am not sure about that rumor, but I did learn that the experts in Canreef much much more is trustable though even though , most of the time, I dont even know who

Thanks...