Should I switch from SS to tube integrated?

I have Quad 12L speakers in my living room and am driving them with the Ayre AX-7e Integrated amp. I have always thought about a tube amplifier and I am starting my research for a tube integrated. The Mystere and the Prima Luna Dialogue Two integrated amps are two possibilities (see below):

http://www.upscaleaudio.com/Mystere-ia21_p_99-645.html
http://www.upscaleaudio.com/DiaLogue-Two-Integrated-Amplifier_p_97-601.html

Do you have any comments on solid state integrated amp vs. a tube integrated? I need to keep the cost under $3k and both of the above integrates do this. I sold my Ayre CX-7e CD player to a friend and so I am looking here also (later). The Prima Luna DiaLogue Two looks very interesting. My only source now is a Magnum Dynalab MD102T FM Tuner running balanced into the Ayre amp.

What the average life of the tubes? Will the tube amplifier require any special maintenance? Will a tube amp drive my 6ohm Quad 12L speakers okay? What other tube integrated amps should I look at? Your comments are requested. Thanks.......