Great at frothing milk and making milk-based espresso drinks.  
Provides hot water on demand for tea.
Easy to use, takes some of the guess work out of making espresso, good for a novice.

The preinfusion feature--you can't disable this.
The portafilter is smaller than a standard professional grade size and produces uneven shots if doing a double into two different cups.
It comes with pressurized filters and shots are average even with the non-pressurized.
It isn't as good looking on the kitchen counter as other machines like the Silvia.

This was my first espresso machine and after using it for a few weeks, I had a bit of buyer's remorse but have kept using the machine for over a year now.  Despite doing research before making this purchase, I admittedly didn't know much about making espresso...only that I liked drinking it and espresso-based drinks.  In hindsight, I wish I had purchased the Rancilio Silvia instead. The Solis was designed to use pressurized filters (that's what comes with the machine). Even when using the after-market non-pressurized filters, I only get an okay (not great) shot of espresso. What the machine is fantastic at is frothing milk.  

Before I purchased the Solis, I had read detailed reviews of the pros/cons of the machine on coffeegeak but I didn't fully understand what they meant until I used the machine. The portafilter is smaller than on the Silvia which uses a standard professional grade size. Also, when pulling a double shot, the espresso comes out unevenly so you end up with one shot being larger than the other. Fortunately, I'm the only one drinking it, so I pull the double into one cup. One other annoying thing is that the Solis does a preinfusion before pulling the actual shot. You can't disable this feature, and I believe it causes the shot to taste over-extracted. This doesn't matter so much in the milk-based drinks, but if you are looking for a good shot of espresso, it will bother you (you should buy the silvia).

This machine is suited for someone who likes milk-based drinks and doesn't want to worry about getting just the right amount of tamp and grind for a decent shot. The pressurized-filters take the guess work out and give you a consistent shot (even if it is only average tasting). Don't waste your money on the non-pressurized after-market filter ($15) in search of a better shot. You might as well just buy the Silvia instead of the Solis if that's what you want. Both machines are the same price (around $600) and from what I've read, the Silvia makes a better espresso but the Solis is better at frothing milk.  I don't know first hand about the Siliva, but I do know that I have made some really good lattes on the Solis.   I've also used it to steam milk for other types of drinks like chai tea lattes and hot chocolate and have been very happy with the results.  

Finally, if you care about aesthetics, the Silvia is better looking than the Solis. You won't find the perfect machine at this price range but the Solis is a decent machine and easy to use.  I had seen photos before purchasing but when I received it, I was a bit disappointed in how cheap the exterior looked. I'm hoping to upgrade to a better machine at some point.

It's been a year since I purchased it, but I think I got it through Whole Latte Love. I didn't have any problems.  It was delivered timely and packaged well.