The portafilter has great build quality, and the pump is quieter than I expected. As long as you get a experienced technician at ESI, their support and knowledge is quite good.
Negative Product Points
I have a January 2003 manufactured 1 group Linea 1AV. Nowhere in any literature that I read, or from the discussion with espressoparts.com did it/anyone know that it comes with the older Mask electronics, not the newer Wizard electronics (only true for the Linea 1 group). The downside to this, at least according to the importer ESI, is that one cannot do pre-infusion. This sounds unbelievable for a $8000 machine. In addition, the 1AV has a 1 inch shorter cup height vs. the 2-4 group lineas. For example, a standard 10 oz. coffee cup does not fit properly underneath the portafilter spout. Also, the training manual does an impossibly poor job in explaining the first power on startup process, i.e. the procedure to bleed the grouphead. Thanks to espressoparts.com for walking me through this. The feet are also somewhat cheap looking- shiny chrome plastic jobbies that make 1980s ford interior chrome look positively plush. Also, the the portafilter basket requires a stiff hand and a tool like a flathead screwdriver to remove. (to put in the backflush disc) It shouldn't be this difficult to remove. Also, the hot water spout spits out water with too much force or too little- it makes it more difficult than necessary to fill a cup with hot water. I am not sure if this involves a defective part, but when i program a water dosage, invariably, the amount of water coming through on subsequent shots is 10%-15% more.
I would mostly agree with the other reviews on coffeegeek in regard to positive points. Rather than duplicate them, the point of my review is to point out some negatives/"things you won't know unless you owned one" not seen elsewhere. One other point is that the machine was going on a bar where the front of the machine would sit on a area that is lower than the back of the machine. It took a bit of thinking and a workaround, but I was able to remove the front legs and it's socket, and replace them with 1 foot long rods attached via large washers and locking nylon nuts. I would disagree with another review on coffeegeek that said the machine takes 6 hours to install. Notwithstanding the grouphead bleed issue (which you won't have because I have now told you about it), installation should take 1-2 hours max. (after all plumbing and electrical is completed, of course)
I bought the machine from Espressoparts.com as a demo unit. The main qualm I have with them is that they told me the machine was 3 months old but in fact it was 14 months old. Come on guys. Their staff has been helpful for the most part, but did not always follow through as they promised. Besides these issues, overall, the buying experience was pretty good.