It's Kaspersky Internet Security, and it is designed to detect malware, so no problem there.
Malwarebytes Anti-Malware couldn't get rid of the fake antivirus thing when I got it on my computer (although it at least detected it), but Kaspersky got rid of it no problem (I didn't have Kaspersky installed when I got infected, otherwise it probably would have blocked it before it got through).
The reason Kaspersky uses more resources is because it is a
tank for realtime protection. Anti-Malware doesn't do realtime, so it won't stop stuff getting on your PC (unless I'm mistaken? I seem to recall that being a paid feature). I've never tried Microsoft Security Essentials, so I can't comment on that, but I've heard good things.
But a lot of the faster scanners are faster because they take shortcuts in what they scan, and also because they're not as tied into the realtime processes of the computer. Kaspersky is definitely a resource hog (!), but it's a fair tradeoff for the protection it gives.
I only recall paying about $55 for a year, and I feel it's been worth it. I used many of the free scanners, and I lost confidence in them after I got infected. Maybe with the right combo like you suggested I could be equally secure, but I'm at the very least getting the same level of protection with Kaspersky, and I don't mind paying the extra for it.