I've had them all in the past. None are optimal for 213/45 SET amps and would be marginal with push-pull amps using those power triodes. But you'll get good tonal sound if not much dynamic life, within the limits of the amps driving small, inefficient speaker designs.
The LS3/5a, which is the speaker I had in longest continuous use over the past 40 years, has the most holistic representation of music of the three speakers you mentioned but it is dynamically throttled. The Spendor is the most accurate of the three, leaner and more neutral than the LS3/5a but missing some of its tonal body and vocal realism. The Soliloquy is the most euphonic of the three, showing the most conscious coloration-by-intent to make an entertaining and forgiving speaker that's still reasonably neutral and images well.
Consider the Audience One, the Silverline SR16 and the Zu Omen Bookshelf or the Zu Omen at your budget if you want to use a small SET or low powered triode p-p amp.
Phil
The LS3/5a, which is the speaker I had in longest continuous use over the past 40 years, has the most holistic representation of music of the three speakers you mentioned but it is dynamically throttled. The Spendor is the most accurate of the three, leaner and more neutral than the LS3/5a but missing some of its tonal body and vocal realism. The Soliloquy is the most euphonic of the three, showing the most conscious coloration-by-intent to make an entertaining and forgiving speaker that's still reasonably neutral and images well.
Consider the Audience One, the Silverline SR16 and the Zu Omen Bookshelf or the Zu Omen at your budget if you want to use a small SET or low powered triode p-p amp.
Phil