Hey Helen,
I play the ref 54 alto (unlaquered) and would recommend it but I played about 8 of them before I found one I liked. The tuning on them can be tough to handle, easier if you have good throat control - i especially found the unlacquered models to be unstable with the tuning over top A, although the sound they make is truely mind-blowing.
One of my students just got a borgani and it is amazing, great action, brilliant intonation, really easy to blow and, most importantly, a rich and full sound! He got a great deal from Allegro in oxford. They are all really well made and seem to be a favourite of top players such as Branford Marsalis and Tim Garland.
Yanni's and Yammi's are also always a good bet - I would also look at the Mauriats for the money, they are a great price compared to other medium range saxs, they have a big sound which works well in larger bands (I play a tenor PM 66R which does the job nicely!).
Sorry for the essay..... hope some of this helps.