Steam pressure from the frothing wand is stronger than the Gaggia Espresso.  Great aesthetics (First thing my guests notice). Easy to clean. Stainless steel boiler.

Comes with the pressurized portafilter.  Smaller-sized portafilter (less than 56mm). Kinda pricey considering it's make is obviously less durable than a Gaggia Espresso (and the Gaggia Espresso is lots cheaper).  Short steam wand.

The Zia's 15-bar pressure is enough to give you good espresso shots but since you are using the pressurized portafilter, you don't quite know if the crema your getting is good or not.

Using the pressurized portafilter will always guarrantee the formation of crema regardless of grind and tamp but if its good crema or not is another story.  The resulting espresso is okay tasting if your gonna use it for americano (better than our local starbucks-produced espresso - at least in my palate) but if you really want to learn how to get the real authentic crema, it's hard to tell if you're doing right or not.  So instead what I do is to go by the 25-second-1-ounce shot rule.  I just count to 25 secs from the time I turn on the brew switch, watch the espresso shot fill up and then I switch it off. It is unfortunate that SAECO doesn't provide the non-pressurized filter here in the Philippines.

With regards to the steam for frothing milk, like I said, the Zia's steam "blasts" are visibly stronger than that of my Gaggia Espresso but the length of time of the sustained steam pressure is suspect.  In the past, I would only be able to steam my 40 deg C milk up to around 70-80 deg C before the green light for the steam disappears then I'll have to wait for the steam pressure to build up again.  I was able to work around this after reading this site's review on the Saeco Via Venetto.  When the steam "green" light goes on, release the steam until the light turns off again (around 25 secs) then that's only when you start frothing / steaming the milk.  Like what the review said, the key is to keep the boiler active.
Thanks to the Via Venetto's review, I am making great frothed milk nowadays and not to mention my preparation time per cup of cappuccino has been cut down by almost a minute.

As for the short steam wand, initially I was using 20 oz pitchers with it but the amount of milk coupled with the size of the pitcher made it hard to froth / steam milk.  I switched to 16 oz pitchers and things are much better (not to mention the wastage of milk is much more controlled).

With regards to aesthetics, the Zia really stands out with it's modern, chic look.  It's the first thing my guests and friends comment when they see my setup.

I was picking between buying the Zia (a.k.a SAECO Gran Crema) and the SAECO Magic Espresso and I picked the Zia because it had a stainless steel boiler as compared to the Magic Espresso's aluminum boiler.
I bought this machine from a local accredited supplier of SAECO and there wasn't any problem much except when I got the machine (I picked it up at the shop), the box didn't have the manual inside and the pannarello didn't come with it (which is something you can do without anyway).