Wait until you get past the initial 4 months without smoke and then see how much better you breathe!
When the tightness in the chest eases way off as well as no longer getting any burnt taste in the mouth you'll know.
The KBox should work out for you at least for the time being especially if that is anything like the Kanger version seen at Kangertech KBOX 40W 18650 Mod
Here I have a few mods that take a single 18650 and run the Panasonic High Drain 3100mah batteries in those. You can either leave the battery in each and charge it there with the cord provided or remove it to charge separately. The ICig V9, Luxyoun 150w wooden box mod, and DovPo 30w "Indestructable" vinyl cased see the batteries left in them. After 2 1/2yrs. with cig alikes including a few disposables, Vamo APVs, eGo batteries, etc. lately the Eleaf iStick 50w 4400mah sealed battery type box mod has been seeing the most use however.
The others will have tanks set up with differing flavors for the quick switch over just for a change of pace at times or for the after dinner variation. You may find that as you go along you will start collecting more gear as well as see the need for more tanks. The 4400mah battery lasts much longer however when placed up against the usual for 18650, 26650 batteries. The longest time is with the 5000mah 18650s I have run across while you wouldn't want those for anything over a 3-15w APV like a Vamo or SMOK ACE since they won't handle too heavy a draw.
Durable longer battery mods include the iStick 50w 4400 mentioned as well as the Innokin MVP2.0 6-11w, MVP 20w(7-20w), just out MVP 3.0 30w all three seeing 2600mah sealed batteries. The SMOK Groove II was a flop tried out here being 3-16w mode with a 3800mah sealed battery but cheap plastic casing and ended up a very short lived mod before grabbing the Innokin heavy weight Titanium/Stainless 3-15w box mod that takes a single Flat Head not Button Top 18650. Reliable as anything can be since Innokin stuff is durable but did find some Panasonic 3400mah Flat Top 18650s. That barely fires an Aspire Atlantis sub ohm tank when all the way up at 15watts.
Actual life spans of mods depend mainly on how any mod is used. With the 20w 2200mah original Eleaf iStick by iSmoka people were stripping out the aluminum threading in a hurry and had fire buttons rattling while none of that was seen here having used the 510/eGo adapter and even adding on the Bending Adapter allowing you to fold up the small tank attached for carrying around in a pocket. The sealed batteries often go sooner from constant recharging where the entire mod has to be replaced while many stay with the replaceable 18650 type for either box mod or APV Vamo style. You have to figure which will work for you the best however since the market is now loaded with either of those types as well as having plenty of mechanical mods. Many who rebuild atomizers, RBA, RDAs, etc. will favor mechs over regulated.