Metal / Progmetal / hardcore guy here....
I have used:
Bergantino NV215
Bergantino NV610
Ampeg SVT-810e
Mesa 215 (older with EV speakers)
Peavey 215
Brooklyn Gear 215
I will say that I have absolutely HATED every 215 I have I have ever played except the Bergantino. They all sounded flubby and awful.
One mistake I see a lot of people making is buying 215's thinking that will somehow improve their low-bass response live, especially if they use a dropped / altered tuning. This is 100% NOT TRUE. Especially considering that what really cuts through a metal mix and makes the bass line apparent (depending in how your guitarists EQ) is the low midrange like 120hz - 220HZ and the high midrange "clank" around 1.2Khz. Generally, I have found that sealed cabs do better for me in a denser mix, and the new Ampeg SVT-810e's (made in china) actually sound MUCH better than the last few years made by SLM.
The problem as I see it this.... making a properly designed ported bass reflex speaker enclosure for bass requires a great deal more "science" and actual design work than most MI manufacturers are willing to put in, as opposed to the relatively simple design needed for sealed cabinets.... Most companies like GK and Fender for example.... its throw two or four like-kind drivers in a box, punch a hole in it an Viola!! Bass cabinet! Of course it will reproduce sound, and it will sound like a bass.... but those of us who have played cabinets from Bergantino and FearFul understand the difference between a ported cab that's just thrown together (even with high quality components and speakers) and a cab that is desgined correctly from the ground up. All over talkbass people, including myself, rave about the Bergantinos and how fantastic they sound... but there's no magic to it, The Bergs are simply designed correctly from the ground up, using the best quality components, computer tuned to the parameters of the drivers (or the drivers specially spec'd for the enclosure), the best possible bracing and electrical components. The fact remains that very few "mass-produced" ported cabinets actually perform anywhere near as well as the boutique ones. The older Ampeg 410HLF would be a great example of a really poorly executed ported speaker cab. Sure its loud, but they sound artificially "deep" and scooped out, and the midrange response is terrible. With this and many other units like it, the tweeter is usually crap, and the crossover is usually cheap and leaves a big "hole" in the frequency spectrum at the X-over point.
Sealed cabinets however, if good speakers are used and at least some respect given to the manufacturers recommended minimum volume, tend to sound pretty good regardless. This, along with the fact that the mechanical damping provided by the internal air volume of the chamber behind the speaker, produce a "tighter" more controlled sound which *usually translates into a better cut in the mix. There's a reason you see than Ampeg 810 tower on 9 out of 10 major rock / metal tours... its loud as hell, sounds great, and cuts through really well.
You can find the Ampeg 810 used all over the place for $600 or less... but if you have the ability to... try to determine the cabinet material before you buy.... for several years these were made with OSB (basically sawdust and glue), and some were made with with particleboard.... and the older ones being the more desireable plywood.... if you're gonna buy a used one try to find a plywood one.
So anyway this post has turned out longer than I intended... You will probably not be happy with a 215, unless you like really muddy, indistinct sound... so I would recommend an 810 of the two choices you listed. If you're going to go with a ported 810 or other ported cabinet... I STRONGLY recommend you go with a Bergantino, or a Genz Benz as a second choice.
