It is a pretty tank and has both a formidable power supply and a rather robust construction but the filtration solution leaves much to be desired.
In comparison I'll look at the 2 gallon Aqueon Evolve and a JBJ Biotope 6 gallon nano.
These three make a nice wide range of poor to great engineering. What will surprise you is the Aqueon is a better system, even with faults, than the Spec.
I have a Spec 2g in my bathroom right now and I have to say its primary failing is the bypass intake slot down towards the bottom of the back wall. This is something that should NEVER be a feature in a tank. The circumstances that make such a port necessary, i.p.e. a water level reduction to the point where circulation through the main skimmer port ceases that could result in an overheat of the pump, make this little hole all the more useless and lethal to fish. It WILL suction materials with more than enough pressure differential to gut any fish you may put in the tank. It is a lethal feature in my opinion, but by far not the only failing of the filtration of this tank.
The lighting is strong and seems to have a spread spectrum, it has run for more than a week and I see no variation between the colors or brightness of the individual LED and it is very powerful. I can see the light clearly at night bouncing around the corner-out of the bathroom-down the hall-off the wall-into the bedroom. Plants will likely love it and it will definitely shine brightly on your swimming flowers. The tensioner screw for the bracket is plastic and very smooth with a nice tool to tighten it, the bracket itself is very robust. The tank's glass is exceptionally clear and I like the frosting in the rear very much, it is a nice effect that still lets you see through to look at the water level. The bigger bio-cubes have useless viewports and ornamental plastic covering this area making it necessary to go behind the unit or open it up and peer with flashlight in order to check on the filtration. The clear plastic lid is, as well as everything else about this tank, robust. It can support weight well, has a feeding/air/light hole that greatly reduces direct reflection glare and allows the light directly onto the water to produce the photochemical benefits such supports.
The filtration assembly is a failure both in general and specifics. The included pump is too large to fit into the hole in two directions and the direction it DOES fit into the system causes the intake plane to be up against the large divider or the back glass. The ginormouganticly huge sponge has a pair of cut-outs for you to place a pouch of carbon and a pouch of ceramic slugs into. The carbon being rendered useless because it can be bypassed and the slugs being rendered useless because of the lower bypass intake. The sponge itself is excellent material but flexes a lot when removed and dumps a large portion of the caught material right down through the pump.
I have to wonder just how dumb the designer is to have not incorporated the very effective technology of the Aquaclear filter's removable rack system. The sponge is too large, the number of intake slots is sufficient for skimming on a 150gph tank and is useless overkill on such a small system. If the large divider were moved forward enough to allow for the filtration rack of an Aquaclear 20 on the left, then a gap between that and the pump turned into an upwards flow segment for a heater and the pump allowed enough room to operate this system could be 10x better than it is.
The Spec has no room at all for a heater in the rear and the lid precludes running one into the tank section... making this aquarium useless for tropical fish, useless for marine fish and its still way way too small for a goldfish (though the sponge is probably large enough to deal with the bio-load.)
The Aqueon Evolve 2 gallon only has one glaring problem in my eyes now that they've fixed the lid issue. It is arranged to use just a small Aqueon filtration card. Once again the carbon in the filter card is heavily bypassed and in this case little more than a joke. Aqueon's filter cards DO however perform well for rough polishing water and are just short of commercial floss in their ability to stop fine grits and dust from being circulated. My only remaining issue with the Aqueon Evolve is the closed boxy area under the filter bracket... it is difficult to get cleaning tools into this area.
The Evolve also has lights, not as refined as the fluval but still bright. I'd not attempt to use the Evolve as a nano-reef system without booster lighting but there is room in the rear to install a heater without having to do a large amount of modification and one could even wedge a fair amount of live rock or a block of sponge in below the filter bracket and put drain holes through the plate below it for an exceptional amount of biological area. The pump is fairly impressive and by far the rear of the tank is easy to fit things into. The only reason I won't own an Evolve is the acrylic construction. I have yet to find an acrylic tank that will last ten years and be as clear and crisp as glass. All in all, whoever designed the Evolve series has got a fair bit of experience with such things and simply had to use the existing Aqueon patents for filtration.
Both the Spec and the Evolve can be made Betta-safe. The Evolve simply needs a half inch thick sheet of sponge attached in front of the skimmer slots just like the Spec but the Spec needs an additional sponge placed over the lower bypass intake if you aren't comfortable with blocking the bypass intake completely.
The JBJ tank, which may not be manufactured any more, is a full blown reef nano tank with the standard three stack filtration system layout but makes use of rigging and modules to arrange it so that maintenance is easy. There is room in the rear for a heater as well as bypass piping for applications such as refugium and protein skimmers but where this unit excels is in the engineering development of all its inherent features and shipped accessories. It is admittedly expensive, far out of the budget of most the people on this forum at around $150.00 setup but in that value you get every penny's worth.
Why did I include the JBJ 6 gallon nano? Because you need to go look at it in real life to understand how rinky-dink the Spec and Evolve really are. We're paying around 50% of the actual cost of the 6 nano for tanks that are supposed to be like it with only a third of its volume, life span, capacity, safety, features and engineering. Might be worth it in the long term to really save up and be serious about a tank you keep a friend in for up to five years?
So my opinion on the Spec and the Evolve are simple. Petco has Marineland Hex-5 tanks for $58.00. They only need a heater and an intake sponge to be Bettariffic. Don't by a Spec or Evolve.