I don't ride MTB, although I do commute on a mountain bike. Finding a good mild weather jacket for commuting has been an exhausting, exhaustive search. I wanted a jacket with handwarmer pockets, a dropped-tail hem, wind resistance, and most specifically, wasn't merely just a shell. A shell, be it a thin windbreaker or a 2.5L rain jacket, provides no separation between the single layer of fabric and your skin, and thus provides no warmth outside of windbreaking. I don't wear longsleeve shirts, and adding a longsleeve midlayer is too much for 55-65° days. More substantial jackets are far too warm. Sure, I could wear a normal style jacket, but I'd give up the dropped tail hem, leaving me unprotected against water spray, cold air drafts, and leave the rest of the world unprotected against the occasional buttcrack flash. The Fox Ranger Fire jacket is the best solution I've found for me. It blocks the wind like a windbreaker should. The fleece adds a bit of warmth but more importantly it gives separation between your skin and the sleeve fabric on your arms. It is NOT a thermal/winter jacket; essentially it lets you wear the jacket with shortsleeves rather than wearing a shell over longsleeves. The sleeves are plenty long, even when you're stretched out (but not overly long). The elastic cuff is pretty narrow, and although there's no adjustment, the longish sleeves mean they'll stay at the wrists - or at least that's the case with me and my skinny wrists. The tail drops down quite a bit, but not comically so. Zipper is 2-way, and although I'd prefer a normal zipper for my purposes, I understand the choice to make it 2-way. Americans will be pleased to know that it's not on the wrong #$%!ing side like so many European and cheap Chinese jackets (ie: the zipper pull will be in your right hand rather than left). The chest pocket is big enough to hold any cellphone (I have an S22 Ultra and there's plenty of room); no "media port". I personally wouldn't bother holding anything in there other than sunglasses and/or hanky or kleenex or napkins, but that's me. The handwarmer pockets have a loose-ish mesh inside, and can be used as vents if you wish (as can the chest pocket). I mainly wanted a place to rest my hands when walking around and a place to store my gloves. It is not a rain jacket. You should do OK light and/or brief rain and with splashes though. Stick your arm under a faucet and water beads and rolls right off, so there might be some sort of DWR on it, although Fox's website says nothing either way. Seams are not taped. I've actually purchased 2 of these jackets; one large, and one extra-large for layering. I'm 6'0" and 180lbs (and shrinking - weight, not height) and not really athletically built. I've got a bit of a gut and moobs, but am otherwise slender (skinny arms, narrow shoulders). My regular jacket size is large, and the Fox large fits me fairly snugly. If you normally wear a large, and you're built like the kind of guy that models for cycling clothing, a large should fit you fine. If you plan to add more than a thin-ish, body-hugging midlayer, you'll want to size up. The XL without layering doesn't look comically big on me - actually it looks fairly normal, but there's a lot of loose fabric to flap around when riding. I wasn't overly concerned about styling, but I appreciate that the jacket doesn't look overly cycling-specific. It does inescapably look like it's meant for some sort of cycling or racing, but you're also not glowing glaringly obvious in neon yellow with reflective stripes and goofy looking back pockets.
