Should I do it?

Hello Everyone.

Okay, so the reason I'm here is not to ask for any technical assistance but instead for opinions. I've been thinking of buying my first MacBook Pro for a while but have a few concerns regarding the switch from Windows OS to OS X, and who better to talk to than the very folks who use these computers regually. So here goes.

I've been a Windows user since... well forever and lately I've been a little frustrated due to Microsoft's latest OS, you may have heard of it, it's called Windows 8. Having used to work as a technician years ago I still occasionally get PC's to fix up for people and often felt that I "need" Windows for what I do, lately I've felt this may not be necessarily true and have been looking for a reason to ditch it due to 8.0. Now here are one or two concerns.

1 - Can a Mac read NTFS hard drives?

I ask this because I usually like to scan mine and other peoples hard drive for malware externally and want to know if the Mac OS can do the same.

2 - How long would a MacBook Pro last me?

My current laptop has lasted five years and is still going well, would an MBP last me that long? or longer even? I've heard people say that the hardware becomes obsolete after around four years due to the latest OS not being compatible anymore, is that generally true?

3 - What if I do need Windows again?

I sometimes run other operating system on VirtualBox, how well does Windows run on Macs virtually? do I still have full Windows capability on Apple's hardware through virtualization if I need to run Windows again.

4 - Questionable Downloading.

I sometimes download from questionable sources like torrents, I know, I know it's bad but it's not often. I know that despite Apple's claims any computer can recieve malware, how well protected would a Mac be against such sources? I run Kaspersky Internet Security on my PC's and am a little bit paranoid about security, would I necessarily need additional protection on a Mac? if so any recommendations?

5 - And finally, are there any common issues I should be aware of with Apple computers before considering the switch? I would also appreciate any advise from other Apple users and possible reasons to consider the switch even further.

Thanks to all for taking the time to read my post and know that any assistance will be appreciated.