I've had a pair for a couple years. As I said in the other thread, last year I put on some weight and had to go to a cheap pair of Reeboks until I could get back into the Tacklas.
The mobility is second to none. Seriously. I tried the pants on and brand new I could do ATG squats in them. They just have the right breaks in the pads.
Best protection out there IMO. Lots of pants have pads in the front of the legs but nothing in the back. 9000's have pads all around. And a lot more padding in the hips.
Bulletproof construction too. Routinely see Tackla pants 10-15 years old in the used shops around here. I see old Tacklas and CCM's (852, etc) and that's it for the older pants.
Weight is a non-factor. They may be a little heavier, but they are right on your core. The further from your core something is (gloves, skates, stick), the more important weight is. Not an issue.
Sizing, I forgot a bit on these. I bought these when I had a 36" waist at size 50 and they were maybe a hair tighter than I'd like. I have a 38" waist now and I'm at the limit with them. Ideally I'd have a 34" waist, when I'm playing at 175-180. But the fact I can squeeze into them is nice. I briefly had a pair of 46 pants when I got down to a 33" waist and it was way too small.
So Guffaw's sizing is right IMO.
30" waist -> 46
32" waist -> 48
34" waist -> 50
36" waist -> 52
Oh, and use dress pant sizing, not jeans. Jean waists always run big.