Make sure you try MSE4 first. I tried it and enjoyed their perspective and radial rulers for speed-lines and the like. I hated nearly everything else about the program. It was mostly a "touch and feel" hate, it just didn't seem to have any flow outside of the rulers. I prefer sketchbook pro for my drawings, and it's even cheaper (better and cheaper? how often does that happen?) But each person has their own tastes. Don't worry about what's "popular", just make sure that it works for you.
You might want to look into Manga Studio 5. It has a new interface and inking engine. Manga Studio 4 and earlier is based on Comic Studio which is being phased out by the publisher, CelSys. Manga Studio 5 is based on their new Clip Studio Paint Pro. Look at the features and more information here: [link]
Looked at it yesterday Heres the catch though, i can only get it from Amazon, and they only have the Mac version and i dont have a Mac. Which was why i was looking into MSE4 though i want to get Manga studio 5
I find it odd Amazon has only a Mac version of Manga Studio and from a reseller. Smith-Micro has a storefront on Amazon. You might wait a while until Amazon offers the Windows version in the next few weeks.
Getting MSE4 now and upgrading later would mean you still have to get a full version for upgrade since version 5 is a different program and you can't do an online electronic "upgrade". The upgrade Smith-Micro is offering is a physical copy.
Like a Kodak one from the 3010(?) series i think, I open it up in MS to save as a PNG because for some reason office doesnt like the the file the printer saves in,and im lazy and press "auto correct" button in office. I don't mess with photoshop much, only to make SAI stuff transparent if needed A good chuck of that hour and a half is draw/fixing the pic before the scan