Hoosier provided a good introductory explanation of LR. For a bit more also written for (and by) a nontechnical layperson check out
my answer to this FAQ.
If a regular resistance 510 atomizer on your 180 mAh 510 battery is continuing to provide a satisfying vaping experience for you, great!
Most of us, however, have embraced the dramatically enhanced and varied world enabled by fat batts like the eGo: 650+ mAh (for many more hours of vaping prior to recharge) and LR atomizers (for increased vapor and TH). And some of the new breed of cartomizers (including LR ones) are excellent, now delivering on the big three (vapor/flavor/TH) while continuing to deliver e-liquid to the atomizer portion much more effectively than cartridges (an advantage they've always had). [A new alternative to cartomizers are the tanks, which, in a sense, are cartridges without polyfill. They are fairly popular although many of us prefer the taste and performance of the cartos.]
Now that Liberty-Flights has exhausted its stock of bargain basement-priced 750 mAh Rivas, two of the best deals on high mAh 510-based fat batts I know of are the $50
1100 mAh Riva from Vapor Junction and the $45
1100 mAh KGO (true 3.7V) from Hoosier E-Cig Supply. Both are two-battery kits. The Riva comes with two attys; the KGO with only one. Since I was only interested in using it with cartos and tanks and I wanted 3.
7 rather than ~3.3V I went with the KGO. Hoosier (the supplier, not my esteemed fellow vet

) also is one of the suppliers, which carries the outstanding
Smok Tech dual coil LR 510 cartomizer (one of the new excellent cartos I mentioned).