New Active Crossover... Bryston 10B, JL audio CR1, Pass Labs XVR1 or First Watt B5?


Okay, so this is a lot of crossovers... Does anyone have experience with any or all of these crossovers? I am looking for the unit with the most transparent high pass out of all of the above:

Bryston 10B
JL audio CR1
Pass Labs XVR1
First Watt B5

This will be for separating my mains from sub in a my 2 channel system.
nemesis1218
I looked into the Pass, but it's over my card limit ;-). The Bryston is too limited in flexibility (slopes, frequencies, etc.). The First Watt B5 is designed specifically for OB loudspeakers and subs, and at any rate is discontinued. So is the B4, which is the x/o you may want (it is VERY flexible: 1st/2nd/3rd/4th-order filters in 25Hz increments from 25Hz to over 6k!). I did, and found myself a used one. It too is, unfortunately, out-of-production. Call Reno Hi-Fi---a major Pass/First Watt retailer: he may know of an available one. 
Marchand makes various types of crossovers.  He even had some tube ones.  Price was reasonable and he even had some tube ones.
There is a 10-B for sale on usaudiomart right now. Manufactured in 2012 so plenty of warranty left. $1100.