I'm sure it will draw the ire of many, but I've never been a huge fan of Chelsea boots. For some reason I think of them as a bit too "Mod," which I know is ridiculous. I just have a mental block. I think my interest in jodhpurs is as close as I'll ever get to Chelseas.
I'm not a fan of jodhpur boots (to be honest, I think they look silly), but if the Mod association is putting you off chelseas, try something more substantial, like RM Williams. Definitely not what I would think of as a sleek mod type of chelsea.
I've been to their physical store on Inis Mor- I have hands on experience with the exact stuff you're looking at. Many of those hand knits may very well be bulletproof, and they have walls stacked floor to ceiling with the hand knit sweaters in various clan designs. Tables stacked high with every design of heavy wool sweater, most in traditional aran patterns, others plainer. A little museum to the sweaters upstairs. Great store.
Just to follow this up, and perhaps to help anyone else looking for an Aran sweater: I ended up getting the traditional heavyweight (machine-made) sweater from Aran Sweater Market. I would have preferred the heavier & more detailed hand-knit but my size wasn't in stock, and I didn't want to wait. Their customer service were very swift in replying to my stock queries & very helpful generally. As for sizing, I generally wear size 36 jackets, so opted for their XS size. It fits really nicely IMO; fairly slim, not at all bulky/loose and the perfect length. I am on the shorter side however, so if you're taller, you need to either stretch the knit out a bit (wool knits will stretch a fair amount; no need to be afraid of this)... or possibly get a larger size to compensate, which might then become too bulky in the chest for you.
The material is a tradtional wool; not super-soft/heavily-processed. However, get all those stereotypes of rough/scratchy/hairy wools out of your mind; it's perfectly soft to the touch and not at all uncomfortable next to the skin. Finally, as has been mentioned above, the machine-made sweaters are only moderately thick; warm certainly, but still good for layering and wearing under a (traditionally-fitting) jacket if you wanted to.
I'm now hankering for a really heavy beast of a hand-knit Aran, as a turtleneck rather than crewneck. I might ask them to make something like that for me at some point; I'm sure they could, if I was prepared to wait.
Overall: a very good sweater, and very good service. Colour me happy. Pics will appear in WAYWRN as some point over the next few days, I'm sure.