An all Parasound system - Good idea?


My brother- in- law visited last weekend and heard my 2 channel system for the first time.  Slightly ocd, he spent much time online and emailed me last night to say he was going to put his own system together and was planning to buy all of his components from Parasound, in part because he thinks a single brand will optimze performance and compatability, and because he is enamored by the John Curl connection. To that end, he plans to buy  a JC2 Preamp, A21 Amp and JC3+ phono amp.

I have told him focus on  speakers first, then source components. That notwithstanding, is the "All Parasound " a good idea to avoid the possibility of components not playing nice together or should he not focus on brand loyalty and shop for "best in class" components instead?

sjtm
Thanks to a very fine seller, Mr. Ricred, I ended up with his JC2 pre amp.  I have owned two A21's and an A23 in addition to the JC2, so
I'm familiar with the Parasound sonic signature. I like it.  With all due respect, I think Mr. Ricred 'made his move too soon'.  After sufficient break in it's hard to find fault with this piece.  For comparison I submit my First Sound PD III vacuum tube pre amp with Emmanual Go's two most recent S upgrades.  While I prefer the FS, the JC2 is not far behind, imho.  I live with both and enjoy each immensely.  Both are dead quiet, musical, spacious, detailed, with deep and wide sound staging, and are just a joy to listen to.  The JC2 is more practical given it has a nice lightweight remote along with balanced and unbalanced inputs and outputs, and is of course solid state. The FS is tubed, no XLR connections, and no remote.  It is however a true dual mono design with an outboard power supply.  Mr. Curl did not stub his toe with the JC2, it belongs with the other well respected Parasound products he designed, again imho. 
JC2 , A21, JC3.
Would love to have all 3 of those. No freakin doubt they are optimized to work well together. For the money, you would have a very hard time finding a different combo that could beat it. Feel free to suggest one. I would be very interested in checking it out..
I have JC3+, JC2 and A21 in my setup. Recently I purchased another A21 and now I use both amps in bridge mode. 
I have JC1s (two) and the JC2 preamp. I would not recommend the JC3 phono as I prefer discrete Class A circuit topography for the phono pre-amp (as does John Curl, BTW). The JC3 uses IC op-amps not Class A discrete designs. I think you will find that JC has commented that the JC3 was a compromise he was not that happy about, but had to live with due to Parasound upper management insistence and the fact that low noise discrete JFETS were getting hard to find and expensive. I myself am using a modified Spectral DMC-10 phono stage from the mid-80's.

To counter some comments above, I find the JC-2 have very good imaging and three dimensionality. It is also very smooth and non-fatiguing. I have used it with both outputs from a Bryston BDP/BDA combo and the phono output from the Spectral DMC-10.  
I currently own the Halo integrated and love it! I always wondered what Halo separates would sound like. I say go for it. If money was no object those would be the components in my system. The A21 will provide enough current to drive any speaker. Properly matching it would be my last concern. In my case I would be more worried about the space. The Halo integrated blends seamlessly with my TV stand. A Halo separate component system would need its rack with a lot of room to breath.