Please save me from an expensive mistake! Sonus Faber Amati Futura longevity concerns...

Thank you so much for all your answers! I will try to address a few things mentioned above:

- @knotscott : You are saying that  ferrofluid replacement should be"Fairly easy to do if the tweeters come out, and the voice coil assembly is removable." How can I assess if this is actually the case with the Futura's tweeters?

- maybe "worried sick" was too strong, "concerned" would be more realistic. I can take care of my emotional balance, I won't loose sleep over future catastrophic failures once the speakers are in my room, but before I use that credit card I want to make sure I'm making a well informed decision.

- I have listened to these speakers before at the dealer and I fell in love with them. I'll get to listen at length again on Friday, with my gear, in the dealer's room before purchasing. My amplifier (Accuphase E470) is perhaps not ideal but I expect it will work well enough as I've heard it driving a pair of Amati Tradition quite well for my ears. My room is pretty small but it seems to eat away a lot of bass so both the Serafino and the Spendor Classic 100 were bass light in it - therefore the Futura's bass will probably be just fine. I have listened to the Amati Tradition at a friend's and to the Serafino at home, both with my own gear, and the midrange was lacking color and magic to my ears and the highs were quite elevated, otherwise yes, I would have went for the Amati Tradition instead.   

- buy back means the speaker belonged to someone else who returned them to the dealer as part of the cost of some other new speakers (like Amati Tradition for example)

- I cannot afford to buy spare tweeters, midrange drivers and crossovers and store them just for peace of mind. A single tweeter is 500 Euro! Also, I don't know how old would those tweeters actually be and if I'm not mistaken the ferrofluid dries out even when the tweeters are kept in storage.

Sorry for the long post, I tried to address most of your points. 

Fair points.  I wasn’t actually suggesting that you buy spares for such an expensive and complicated speaker. ;-)  You say you love the sound, the woofers have been replaced so they didn’t seem to spoil what you like about the speaker, and they should last for a long time.  That leaves the tweeters.  I understand your concern but I would ask the dealer if they can or should be serviced, and how much that would cost down the road.  OTOH, if this is always going to be a worry, like with one commenter above, then stop right now and move on.

Something that does bother me a bit, however, is when you say that the other SF and the Spendor 100 were "bass light" in your small room.  Perhaps some treatemnt woukld help, but I can't help wondering if you're buying too much speaker for the room.

Unfortunately past experiences have made it clear to me that the dealer will not always keep his word.

Please correct me if I'm wrong but "too much speaker for a room" usually results in uneven, excessive and uncontrolled bass, not in an overall feeling of lack of bass. Maybe I'm placing the speakers in a null, but that's where the midrange and highs sound the best, about 1,2m out in the room (measured from the front baffle to the back wall) on the long wall.

Somebody told me that  "you have to check if the tweeter you want to repair is easy to open. Some tweeters have a ‘click system’, or are glued together, and therefore barely serviceable" . Anyone knows if the tweeters in the Futura are serviceable?

Not sure where I've got this information from a while ago, I might be wrong, but the tweeter might be a (modified?) Scan-Speak Classic D2905/970000 while the midrange driver might be a modified Scanspeak 18W8545. FWIW

@donquichotte - @knotscott : You are saying that  ferrofluid replacement should be"Fairly easy to do if the tweeters come out, and the voice coil assembly is removable." How can I assess if this is actually the case with the Futura's tweeters?

I'd ask the dealer and/or Sonus Faber