I owned a an active set of 5140s (upgraded with Espek drivers; only real difference at that point was absence of Espek cabinet modifications)run with three LK100s (and before that active Keilidhs with same amps). Also have listended extensively to active Kabers (again with LK100s) and active Keltics (with Klouts)at local audio store that was a major US Linn dealer before it went out of business. The 5140/Espeks had better base than the Kabers, not only because it was a 3-way design, but also because it was ported rather than sealed; however, the bass lacked good integration and overall the speaker lacked the exceptional coherence of the Kabers. The Kabers are one of my favorite Linn speaker of all time, precisely because of the seemless driver integration and coherence (part of which comes from a sealed speaker design), although it was admittedly anemic in the bass. The 5140/Espeks sacrificed some of the specialness of the Kabers to meet the demands of the home theater market. The Keltic/Klout combination was also great, but a different level of expense. The real problem with that generation of Linn speakers, in my opinion, was the common ceramic tweeter shared by all of the models; it had a closed in sound. My current non-Linn speakers (gave the Linn system to my dad) use Scanspeak Revelators and the difference is night and day in terms of openess (another example is the Dynaudio Esotar, which is arguably even better). My current view is that, on a limited budget, you can generally get much better sound devoting the cost of the extra amps necessary for an active configuration to higher quality speakers and a higher quality single amp; the system will admittedly miss some of the addictive dynamics of an active Linn set-up, but that is off-set by the far better refinement of the sound. My current amp/speaker combination (Pass XA30.5 amp with North Creek Catamounts) beets the pants off my old active Linn system (not even close), but did not cost that much more (although I will admit it does lack the punchiness of my old system).
For what it is worth, the Klout is, in my opinion, a far better amplifier than the LK100 in terms of transparency and punch; my old dealer said he liked it more than the entry-level Levinson amps, e.g. 331.
Best of luck.