Hi Grannyring, you are exsperienced and know better there is allot more to it than just plopping in a different pre-amp.
Tthean, you have only mentioned these two specific pre-amps so you oobviously have done your home work in what they have to offer along with your needs are and both do such, next would be to get them into your own set-up and live with them for a while to evaluate strengths and weeknesses and what you prefer in your own set-up.
Other pces in your set-up might need to be changed to get your over all preferred sound, that will be the big question.
Best to look at others set-ups whom have the same and see what other associated gear they have paired up and if such compares to what you have currently then see if you can go for a listen.
It's the joys of this hobby, never ending good luck in your journey.