Dear Eagle,
If DLPC (Downlink power control) is used in the cell, there is no issue to perform HO from BCCH TRX to Non BCCH TRX and the dicision from the network side will be better than being in BCCH TRX, if it was need to increase the power to the same level as bcch trx it will do it, if there was good radio environment and was no need to increase the power so the call will be continued in less power and the connection gets better quality than being in BCCH TRX