I believe the PS Audio Perfectwave w/bridge would be another (likely better) option but you'd be looking at slightly over $2000 used for the MKII and a few hundred less for the MK1. The one's you are looking at are likely very decent options for your needs but probably not much better (if at all) than your current solution. The SBT through the Cambridge Audio 740 or 840C isn't a bad deal at all. Maybe you'd be better off upgrading the preamp/amp if you feel that's a weak link?
I'm in a similar position using the networked SBT into a PS Audio NuWave (which replaced a CA 840C, BTW) and I've been looking for another networked solution to get the SBT out of the loop. I've looked at the same products you have, as well as the Rendu, and I just felt they wouldn't be that much of an upgrade, if any, so my next step will likely be the Perfectwave. Then again I guess it depends on whether you are looking to just consolidate into less gear or strictly going for the next SQ level.
The good thing about upgrading from the SBT though is that you can usually get quite a bit more than you paid for them due to the fact that they are discontinued but still very sought after.
I'm in a similar position using the networked SBT into a PS Audio NuWave (which replaced a CA 840C, BTW) and I've been looking for another networked solution to get the SBT out of the loop. I've looked at the same products you have, as well as the Rendu, and I just felt they wouldn't be that much of an upgrade, if any, so my next step will likely be the Perfectwave. Then again I guess it depends on whether you are looking to just consolidate into less gear or strictly going for the next SQ level.
The good thing about upgrading from the SBT though is that you can usually get quite a bit more than you paid for them due to the fact that they are discontinued but still very sought after.