Yeah the quad is excellent, and I'd certainly recommend an upgrade from a 100w max mod, I like it best at 110-125w.
I just got my Smok Xcube II mod in the mail today, have to say I like it better than my Sigelei 150w mod. TC is nice, doubt I'll use it (rather dial in my coil and have fun doing that) as I don't deal with burnt coils much. If I used primarily premade coils it may be worth it to prevent me from burning them up but ehh... I like power mode well enough.
Why I like this new mod, well it feels better in my hand with the rounded edges and slightly smaller box. It's display is nice and has some interesting features that are pretty cool (can adjust to have extra power initially, which is great for slower ramp up coils, or conversely can adjust to have a slower ramp up. Then it also counts your intakes, and times them which is cool. Then it just looks cooler, the bar to activate is nice over the button. And, it was cheaper than my sigelei 150w, granted it took a month to get here though as I ordered it from China. It has a neat LED light under the activation bar which can be adjusted for colors with a blutooth app. Just overall appearance it's far above the sigelei, feel again better, and functionality superior.
All that said, with the TFV4 premade coils the best of the bunch (excluding TC options I haven't tried) is the Quad coil and while it says 140w realistically if you want to chain vape a bit, you won't want to exceed 130w, it says 140w but if you do that and take 2-3 successive hits you'll end up with a burnt taste as the juice simply can't keep up... or at least the juices I use (typically higher VG).
For myself I run a modified single RBA build (drilled out extra juice flow as well as widened the holes in the deck to allow a more robust coil) and I can run that bad boy up to the 180w that this mod allows without a problem. The taste with some juices suffers at higher watts though, more simple flavors ~100-110w is best, and more complex I enjoy higher wattages.
Anyways now that I have this I wish I would have gotten it to start, well, excluding the shipping time, I am glad I got the Sigelei which arrived in a week but I'm glad I upgraded (was running the Sigelei for about 2 months)
Looking for a future proof mod, the Smok XCube II is a solid option IMO. I got mine on sale for about $45. There are probably better ones out there with say the DNA200 and such (only read about them) but this is a solid option and considering no tank + premade coils can really handle anything near it's max, well, you're going to be sitting pretty for quite some time.