I've used both SNS 2.0 and SNS XL in my 26. Originally I got the 2.0 with the removable water tray because the XL was no longer being produced. Once the XL went back into production, I CL'd the 2.0 and got the XL. I figure Weberitis ended up costing me a good 70 bucks by the time I got the XL, which to your point is the most expensive option.
Comparing the two models, I like how the XL is welded and seemingly more heavy duty. My 2.0 was pop-riveted together which didn't inspire a ton of confidence. On the other hand, in retrospect I really appreciated the removable water tray of the 2.0. I never bothered to do a coal count, but from what I've understood the 2.0 (minus water tray) holds just about the same amount of charcoal as the XL. Doing briskets, I've taken a fully loaded SNS XL 10+ without having to reload it. The 2.0 should easily be able to go 6-8 hours.
It would be interesting for someone to explore how many KBB briquettes each fits, XL, 2.0 and 2.0 minus water tray, just so we can all have one more semi-useless piece of information in our heads.