In my opinion you made a good choice. The boggers move earth very well, but thats all they do.They do not move your rig forward, they just dig holes....it's worse in snow. The only time they work is if you already have forwad momentum and are going in a straight line.
The tread depth and toughness of the SX makes it a great choice for the NW. There is also a little bit of sidewall lugs that look cool.
I agree they're strong but..
36x12.5 15- SX 6 ply 22/32" tread 35.9" tall
36x12.5 15 TSL 8 ply 24/32" tread 36.3" tall
But the SX side walls do look cooler