It's a beautiful beast of boiler.  Although we've had it less than a month, we're falling in love with learning to make espresso all over again.  We've used small consumer machines (Oscar, Krups) and we've got a Linea 2AV at our shop.  We bought the CJ (reservoir/vibe pump) for catering and as a store backup, but when we need it home, we'll use it there too.  It can pump out the volume, is reasonably temp stable compared to HXs and steams beautifully.  It's easy to adjust and very responsive.  The best part is it does more with less coffee.

The steam wand configuration and nozzle is a bit of a pain to clean - if you're not careful, crud can stick to the small ridge where the nozzle meets the wand.  So far, that's the only significant complaint.

Having worked primarily on commercial equipment like the Linea, there was a small learning curve with the CJ, especially since we opted for the reservoir version.  If not careful in filling/starting it up and immersing the water filter, air bubbles can form which will make some significant noise until cleared out.  

Our CJ has a 2bar variance on boiler pressure - we've set the high end at 11 for now, so the low end is at 9.  This may seem a little high, but it's working wonders with Black Cat.  Rich, chocolaty shots, beautiful to look at and silky body - and this using ~15.5g in a double vs. the 18g double we use on the Linea.  The holes on the CJ baskets are much smaller than the stock LM baskets, so we can use a finer grind.  (We're now dying to try these baskets on the Linea to see what we get!).

Steaming is good.   The knob seems a bit less responsive than the Linea - there doesn't appear to be much difference between a quarter turn, a half turn and a full turn of the steam knob.  When we first opened up the steam wand without a pitcher underneath the steam appeared even more forceful than the Linea.  However, in actual steaming, it's got a little less power than the Linea, and we're still adjusting to it.  Didn't stop us from making some sloppy rosettes the first couple of tries.  It's certainly capable of good latte steaming.  We're still working on the caps.  We've heard of mods using a Spaziale wand and nozzle and that may be something we consider in the future.

We bought from Espresso d'Milan, which is co-owned by Todd-Michael formerly of WLL.  Todd is fair and goes out of his way to match the equipment to the job.  He made an excellent case for this unit when we were originally looking at something we could use for catering, guest espressos and home use.  For what we're using this for we'll likely match it with a La Grinta grinder which will be an awesome catering setup.