Welcome to the bass and baritone sax review section.
Of the 'big three' saxes, the baritone is the grand-daddy. Not just in terms of size and pitch, but also in terms of history - it's reputed that the first saxophone ever built in around 1840 was a baritone...coming out of Adolph Sax's experiments with bass clarinets.
For many years the baritone was consigned to the typical role assigned to bass instruments - that of pounding out a leaden bass line, with perhaps the occasional foray into something resembling a melody line. But all that has changed, and the baritone has not only come out of the closet...it's come out wearing a pretty sharp suit.

Perhaps the most obvious drawback of the baritone is its size and weight. In that sense it limits the age at which a student can effectively handle a bari - though there are options such as stands and special straps that can make life a little easier.
It's often thought too that such a large instrument requires a great deal of puff to make it play - but this isn't the case. It's actually quite surprising how delicate a blow the baritone can be, and it's only when you really have to push it that you might find it taxes you.

As mentioned, for a long time the baritone fulfilled the role of a bass instrument - simply filling in where there was a lack of a traditional string bass - but during the age of the Palm Court Orchestras of the 1920's the baritone began to make tentative steps into the limelight as a soloing instrument in its own right. Admittedly much of this was in the 'novelty' genre, but it was at least a step in the right direction.

It took a few more years before the bari sax established itself as a viable lead or section instrument, most notably in the hand of Harry Carney - but perhaps the man most responsible for altering the status of the bari was the great Gerry Mulligan, who proved once and for all that the baritone was both a lithe and expressive performer.
Since then, many composers have taken advantage of the bari's low end growl...and quite a few have made use of its surprisingly wide top end too ( though some traditionalists would argue that there's not much point in buying a bari if all you want to do is play high notes! ).

In more recent years the bari has made significant inroads in less formal genres of music - there's barely a horn section in a soul band that would consider itself complete without a bari, and even the pop charts have fallen under its charm as demonstrated by the late Ronnie Ross's playing with the group "Matt Bianco".

Price has always been a limiting factor for baritones - they're big, and thus expensive ( though, conversely, sopranos are often just as expensive ), but it doesn't seem to have prevented them becoming a firm favourite with sax players who wish to 'double' ( to play another instrument aside from their main one ).

As for the bass sax, the outrageous size, price and thus rarity of the horn has left it somewhat out in the cold - and yet it too has capabilities as yet perhaps undiscovered. It also had its champion in the form of Adrian Rollini, who did much to dismiss the notion that the bass sax was little more than a comedy instrument. Likewise, Boyd Raeburn raised its profile by dint of his being a big-band leader who sported a bass sax.
It still remains largely confined to small groups of the New Orleans and Palm Court genre - and yet it also remains perhaps the only horn that every sax player would love to own, provided they could find one cheaply enough!
The problem is exactly that though - finding one. Modern basses are hideously expensive ( £5000 + ), and old basses, though often available, are usually in pretty poor shape.