It's modest on the counter, it makes excellent espresso, it steams milk to a fine microfoam, it's solid and reliable.
Positive Product Points
Makes consistently good espresso. Powerful steam for milk drinks. Doesn't show spots! When you wipe it down, you realize how much coffee grunge is hidden day to day.
Negative Product Points
Not sexy looking, just cool at best. Needs to have some steam released a few minutes before brewing (even with the steam release valve added). No dials — requires portafilter pressure gauge for assessment. Noisy vibe pump, but that's just how vibes are.
I've had my Oscar for a year and a half. Mine is not quite a stock model — I added a steam release valve myself (a little assembly bought from Chris Coffee), and sent it back to Chris to have a true over-pressure valve added (the OPV that comes on the machine is really just a safety valve, I believe). The added OPV may not have been necessary at all. It is quite likely that, if I had waited until I had my 'hand skills' under control, the addition of the OPV would have made no significant difference. The OPV brought the presure down from about 10.25 to 9.5.
I've got it on a timer every morning of the week, and it makes consistently good espressos and machiottos and lattes every day for me, my wife, and kids when they're home. I really couldn't be happier with it for the price.
I roast (most of) my own coffee (in a Cafe Rosto). I've got a Cimballi Junior grinder, which is just an excellent machine.
After about a year, a couple of wire connectors at the end of the heating tank melted, the insulation smoked, and the machine was on the fritz until I could put on new connectors from Ace Hardware. I keep an eye on them now and then to make sure they're not being distressed.
I don't really understand the need to release steam from the steam wand in order to fully heat the machine, but the need seems to be real. I don't consider it a problem; releasing a little blast of steam is just the first thing I do in the morning, and by the time I've added water to the reservoir, warmed a cup and ground some coffee, the Oscar is up to temp.
I have never had the equipment to measure brew temperature. I've gotten used to the 'water dance' that I see when the portafilter is removed and the brew water is overheated. As soon as the dance settles, I load the portafilter and go.
The Oscar performs true mechanical preinfusion, which may give it some advantage over the E-61 'progressive' preinfusion. At a good grind level (for a 26 second shot), the water first breaks through at about 12 seconds.
The gasket had gotten hard from the heat after about a year, and I ordered two more for few dollars. I noticed a recent review mentioned problems locking in the portafilter, but hardened gaskets are a fact of life, and replacements are cheap, fairly easy to install, and immediately provide the seal that the machine originally came with.
When the Oscar is cooled off in the evening, I turn it on briefly to exercise the vibe pump so it will come on perfectly silently at 5:00 a.m. A rotary pump would be nice if I had some good reason to upgrade, but I don't believe any system would give me appreciably better coffee. A pump pressure dial would be nice, but a portafilter gauge does just as well and once the pressure's set the gauge is mostly good for looks. A tank pressure gauge might be interesting, but again I doubt it would make a difference in my coffee.
In a way, the best thing about the Oscar (as a contender) is it's modesty. It does the job without any ostentation. It's just a well built, conservatively designed machine. It's a little like the beautiful scientist behind her glasses. She just looks steady but she's really sweet.
Chris' Coffee has the attitude and experience to make buying and maintaining a machine as easy as if you'd bought it in your neighborhood. Chris held my hand on a couple of phone calls when I just could not get the coffee under control.
I would look for a machine that Chris sells if I decided to go for a new one, and would regret it if I fell for a machine Chris did not sell.