I'm buoyed by the reports of fairly flat in-room FR of recent Walshes. I'm certainly intrigued.
Now, if the goal of hi-fi [to the source material] is truly that, then good active speakers are far superior to any passive. Audiophiles' preference for loudspeakers with passive crossovers over actives is a matter of not being used to the *far* lower distortion of good active speakers, and unwillingness to get rid of those phallic symbols that are audiphile amplifiers.
ATC's outstanding reputation precedes them as evidenced by nothing but excellent reviews from professionals and amateur audiophile magazine reviewers alike. This is supported by the usual and erroneous criticism that ATCs aren't "musical," as if a component could have that characteristic to begin with. "Musical" means the response slowing, phase problems, sloppier bass response, and much higher general distortion of passive speakers as driven by amplifiers that have difficulty controlling the drives through passive crossovers. Some folks are used to this and therefore prefer it; you won't hardly find any top professionals who still use passive monitors to really hear what is on recordings.
Audiophiles are about 30 years out of date. Professional speaker and audio technology is so far ahead of audiophile technology it's silly; I suggest you explore Event Opals, K&H, and many others, including AVI (for a speaker system with SOTA sound that makes redundant a whole system), Emerald Physics (their speakers are at the top of the curve technologically) and the superior Linkwitz Orion system.
Passive loudspeakers are seriously outdated technology; imagine if your new cars still came with pushrods, solid rear axles, sliding pillar front suspension, and drum brakes. Passive loudspeakers with big, overbuilt amps (only necessary to overcome the detrimentals of passive crossovers) and preamps are nothing more than that.
The biggest joke in audiophilia is Audio Note and their ridiculous $100K or whatever it is two-way with the massive silver-loaded passive crossovers; as if you could ever maker a silk purse from a sow's ear. If that company wasn't so steadfastly regressive, it would have made a far supeior version of that speaker for far cheaper by making it active with dedicated amplifiers. Period. That mega-buck crossover still has an order of magnitude higher distortion than an electronic one. It would be like Ford selling a version of the Mustang with a silver-plated and diamond crusted solid rear axle and claim it is better than the stock car's solid rear axle. 20 times more expensive than independant rear suspension, and still nowhere near as good. The same goes for Wailson Audio and their way-over priced elephant coffins, and all the other purveyors of high-priced passive speakers.