Bryston preamps

Bryston is renowned for their amps obviously. I have a BP 25 into a 14b3 but have a chance to upgrade now to a BP 26 or 17. Should I instead invest in a tube preamp (5k budget) or stick with bryston for synergy. Audio Advisor has Parasound and Vincent. A forum post I read about the Para sound said it might sound to lean With the bryston. I'm looking to buy new this time around. Thanks for any input. Huh there is the George Lightspeed to ponder.