Bryston amps Bridged3B's or 4B?

I currently have a 3BST that I like a lot. However I need more power. Has anyone had the experience of comparing a pair of bridged 3B's to a 4B?
I have not compared but it is generally better to get a purpose built bigger amp than bridge. If you bridge then each amp sees half the load which can mean excessive current demand for the all too common low impedance speakers sold today. Another issue can be DC offset. Both these issues can make the amp run very hot...

What speakers are you driving?
I recommend you post the same question over on the Bryston Owners circle on AudioCircle. There's a lot of expert Bryston knowledge there--and probably someone who's tried just what you're asking about.
Post removed 
Doesn't Bryston have a bridge switch on the back of their amps? My 3B does.
Are your speakers bi-wireable?

If so, you could go the vertical bi-amping route, without having to bridge (and lose power into lower ohms as Bob R. suggests).

Drive the tweeters or tweeter/mids with the 3B, and get another 3B or even better a 4B for the woofers.
i had the same problem.went with the 14bsst,,,problem solved.go withn the bigger amp and dont look back.
Thanks for your responses. To Twoleftears, great idea, I will try that. To Rwwear yes my 3B has a bridging switch also. I have Vandersteens and I don't know how the speaker load varies.
Post removed 
If you search the Vandersteen FAQ page you'll find quite a lot on bi-amping. RV explains that when an amp is only connected to the tweeter/mid terminal, it "sees" the caps protecting the speakers but not the resistive load provided by the woofer. This situation can in turn cause the amp--particularly ss amps--to oscillate wildly, which can cause speaker damage (not covered under warranty).

RV seems to like monoblocks snuggled close up to each speaker. Still, I'm not quite sure about the need for more power, as RV repeatedly makes mention of 100W or at most 200W amps being more than sufficient, and Brystons aren't exactly current-impaired...
Try the Bryston switched to mono on one speaker and see if it works well.