Been taking Reishi (and intermittently Chaga) for a few years now, either 2 or 3, can't remember exactly. My allergies are almost totally gone. I used to be allergic mainly to pollen, dust, cats and mold. Pollen allergies happened every year and resulted in me constantly sneezing and needing to carry multiple handkerchiefs around every day. Occasionally I would need to retire to a dark room, as my eyes couldn't cope with light and I needed to sleep the headache off.
My body's response to pollen is interesting - when a new type of pollen appears for the first time during the year (like birch pollen early in the year or grass pollen later), my nose will itch and I may sneeze, maybe for a whole day, before my body/immune system adjusts and then I have no further adverse response. It's like your immune system needs to play with the pollen for a while before deciding what to do with it, before neutralising its effects. After that, I can occasionally still 'smell' pollen and feel it going up my nose on a high pollen day, but nothing happens. Keep expecting something to happen, but doesn't. Dust I now seem to be completely immune from, unless it goes down my throat (couple of times I've drunk out of a wine glass that had dust it it, my chest will still get wheezy), and I think mold on nuts has the same effect.
I see the OP is in London, I am in the UK as well so can recommend Myconutri as a supplier, made in the UK, I order online from mushroomnutrition.com. They are dual-extract products. That's my main intake. I also stock up on 'Four Sigmatic' reishi 'mushroom drinks' (I buy them in Planet Organic when I am in London), £20 for a box of 20 sachets but you can dilute them down so that one sachet makes two drinks, still a 500mg dose of dual-extract product per cup. Will also occasionally buy the Chaga version, but don't use that at night as it will keep you awake (the whole night).
Also took Cordyceps for a while before dropping it, as there are only so many pills you can take. Combined with Rhodiola and/or Eleuthero, when I used to go running it definitely increased oxygen utilisation, like you could gulp more air down as you ran. But if you're just running to keep fit then it may be overkill.
Energy-wise, Chaga definitely keeps me awake, but doesn't energise me (Rhodiola and Eleuthero combined will also do the same thing but with a discernible 'boost', a kind of light-headed feeling where you can imagine never going to sleep ever again).
A couple of years ago, while I wasn't working and had time on my hands, I tried taking a bunch of other stuff, but mushrooms (and magnesium) are the only ones I've stayed with. Lots of shiitake omelettes as well.
