I guess I'm not too much help, as like you, the only avet I own at the moment is the SX model.
I've only used it for one trip so far, but for the price it seems to be an excellent reel. The one problem with avets that I do see for jigging, is the lack of an anti-reverse on the reel. This is just a minor nuisance, not a deal breaker IMO. Higher end level winds such as accurate and JM don't have this issue, and as such are better suited for jigging. Again, just my opinion (not that it matters much!).
I have taken the sx (ss 5.3 model) out to winter harbour a few weeks ago, to try along with my new JM jigging rod. The biggest fish I caught was a 22lb halibut, but this wasn't a problem for the reel. The reel ain't no chicken winch with the higher gears, but I'm a pump and reel kind of guy, so lower gears aren't that necessary for my style of fishing.
If you want to put some decent drag on the fish, I suggest looking at the avet JX model and up, or their new raptor series. The raptor series is more expensive, but has a dual drag system rather then a single. The dual drag system has a few advantages over the regular series, but at a higher expense. If you want to have a better drag system in a lighter smaller reel, I say go for it.
If you don't mind spending a few $$$, companies such as accurate, JM, etc. make great level wind reels that are purpose built for jigging. Small, light and with powerful drags, they are pretty nice units.