Self-publish or go traditional?

Whilst I’m waiting for feedback from my first test readers I’ve been exploring the different opportunities for publishing my first novel.
I had originally planned to go down the traditional agent/publisher route, a notoriously difficult and lengthy process that seems to require perseverance, patience, a strong stomach for rejection and no small amount of luck. J K Rowling’s excellent novel The Cuckoo’s Calling was rejected numerous times by literary agents when she submitted it anonymously after completing the Harry Potter books, so what chance do us mere mortals have?
I attended a Guardian Masterclass earlier this year given by agent Juliet Mushens at United Talent and what she said was inspiring but left me feeling a little bemused - does it really take up to five years for a new novelist to hit the bookshelves? I’m used to the few weeks or months of magazine schedules, but hearing of several years after a book deal is signed before publication has made me think twice.
I have decided to take a two-pronged approach: I’ll submit the first three chapters and a synopsis of my final draft to agencies to see if anyone bites, but I’ll also self-publish (mainly for friends) on the Kindle App platform this summer, probably with a CreateSpace print edition too later in the year. What is more, by going electronic I can make revisions to the book once I start to get feedback and reviews at no cost or delay - that’s a big plus for me as I’m still learning.
I’m not a huge fan of Kindles - I don’t own one and prefer to read on paper. Having said that, I do read my news, magazines and occasionally books on my iPad, so I do appreciate the advantages of e-reading and believe that the two forms are compatible rather than competitive - different people have differing requirements and have choice, which is the important thing.
Publishing via Kindle doesn’t appear to restrict opportunities with conventional publishers either: the Fifty Shades books and The Martian started off as self-published efforts and it hasn't hurt either of their sales.
So I plan to explore both routes. At least I can say with some certainty that I’ll have something out this summer for people to read and, hopefully, enjoy. Not long now.