To throw in my $.02 (or maybe more like $.01, or $1, depending on your point of view :-) by way of affirming that we sometimes hear things a little differently depending on our ears and gear:
I own a DNA-125, and have no experience with the 225 or the particular Ayre in question. Based on what I hear in my system, I've been surprised that some reviews have described the 125/225 (which are more similar to each other than either is to the 500; some folks seem to feel the 125 even sounds a little better than the 225 in certain ways, lower power notwithstanding) as being a bit forward and bright. I actually find it to be slightly mellow and laid-back if anything.
(That's through Thiel 2.2's via Au24 SC, powered with a Shunyata Sidewinder PC from an ExactPower EP15, and fed from a Levinson 380S via van den Hul The Second. Experimentation has shown that the 125 can in some ways prefer a bit warmer-sounding SC and PC in this setup, but I normally don't bother to switch everything around when I insert it, and it still sounds fine.)
I would not mistake the 125 for a top-flight amp - it has good authority and ease for its price/size, just not world-class - but it really does very little wrong: a touch of boxiness, generally not quite as airy, open, fast, or extended (or transparent) as better amps. IMPORTANT: Auditioners must be cautioned that this amp will sound unrealistically on the flat, hard, cold and grainy side if not given adequate warm-up, and should ideally be heard with at least 2 days of continuous power-on beforehand (in my system the 125 serves as the back-up to tubed monoblocks, but when I do use it I don't turn it off). If that's not possible, then give it at least 2 hours playing music before doing critical listening.
The strengths of this amp, to me, include remarkably pure and natural harmonic structure for what is after all a budget amp in audiophile terms (and a class A/B SS one at that). Bass weight/drive and overall loudness capability are also surprisingly good - I don't feel like I would ever need the 225 in my 14 x 23 x 8 room and with my speakers, even for playing high-energy rock so the neighbors can hear. Imaging is notably 3D and rock-solid (though not the largest, if that's what one desires), with good - not exagerated - focus, and as mentioned the soundstage is deep, if not quite as tall and wide as can be had.
Tonal balance is commendably full and neutral, except for some lack of ultimate extension at the top which subtracts a tad from sparkle and air, and only a hint of a slightly pinched or nasal quality in the lower treble that's never obtrusive, but simply keeps things like saxophone or ride cymbal just a tad on the closed-in side (or from fully blooming if you subscribe to that word). This is really quite minor though, and far from the worst thing you could hear out of such an amp, especially considering that the harmonic structure remains so benign.
Textures are smooth and clear and free from artifacts either niggling or gross. Coherence and timing are unified and consistent throughout the spectrum - I don't hear any phasiness, articulation is fine, and spatial deliniation is well-defined and -integrated. Driver control seems very good at the least - images don't cling to the speakers and show perfectly adequate if not outstanding separation - and again I find depth of field to be one of the amp's stronger attributes. Abundant clarity and cleanliness is always in evidence, no spitting or splashing.
The 125 falls behind my reference amps (VTL 185's) in terms of overall liveliness, micro-dynamic expressiveness, and macro-dynamic impact, and it's not as deeply resolving or quite as detailed in portraying timbral color. Transparency is a bit curtailed, details such as cymbal decays or mouth technique not as extensively excavated. Its feet aren't made of clay or anything, but better amps can be a touch quicker and more finely shaded of transient nuance, though the 125 is excellent in terms of lack of overhang. I don't hear the hardness, glare, excessive edginess or chestiness, congestion, flat aspect, mistiness, darkness, dodgy imaging, detached sense of reverberent ambience, or anything else that I might have expected in a SS amp at this price. Just a very residual degree of 'mechanicalness' - a little less organic/present/alive/fully-developed when compared to a better amp - which engenders a small sense of remove or relative diminishment of physical 'action', but not nearly so much as to be uninvolving. I will dance and play air-drums to this amp, and can feel the emotiveness of singers clearly conveyed. It has never made me wince or wander off, and often draws me in. But it can't quite envelop, sweep away, caress, or hard-wire to the brain the way the tube mono's can. Big duh.
Perhaps the McCormack upgrades largely address the shortcomings, but they are not bothersome when the amp is considered on its own. It may not be SOTA, but it doesn't ring a false note, and is easily enjoyable all around. It's also entirely comfortable driving 4 ohms and playing loud (and runs cool doing so). Maybe the 225 would ameliorate some of the slight sense of restraint (NOT strain) in the 125, I don't know (though it seems reasonable to assume), but I wouldn't dismiss the less-expensive 125 out of hand if your speakers are at least of average sensitivity and your room, speaker cabinets, and woofer diameters are mid-sized or less. Most importantly, this amp sounds real and honest, neither adding to nor taking away from the sonic presentation in ways that could compromise the relaxed musicality that's essential to believability from gear and trust from the listener.
IMO it's a highly competent bargain at its price, but I don't have wide enough exposure to rank it among its competitors. All I can do is tell you what I hear. End of off-topic review :-)
