I went down the guest article road once and ended up canning it. Not that it was hard to get writers but the quality of work was awful and I had to really research these people as time and time again I'd find copy & paste work passed off as their own. Most guest bloggers don't just blog for "exposure" or backlinks they blog to drop affiliate code on your site; place links to sites which don't relate to your own (Googs doesn't like that and get suspicious); and cheat their way into search engines off the back of your site's good name - be wary.
If you have the money and are willing to pay for good writers or original content matching your niche without any strings attached (no linking etc) then I see nothing wrong with that all. Especially on a blog generating good income for some funds to be set aside to pay for more good quality content.
Cross posting with another site in your niche is another pretty good way to generate content from other writers for variety etc (although, I don't do this either). My "guest posts" these days come from people I know and trust but most of my content is written by me. I often find great ideas from forum members and "steal" their content (from my forum) to add to my blog in my words.
My latest forum has an an articles section
(Xenzine) it's designed as per the add-on's intent which is to open article writing to forum members - this is an excellent add-on BTW and it allows vetting of content before release plus it looks good. Unfortunately, my small membership base on this particular forum is so small and lethargic that I still end up being the only one populating the articles section lol but in time I hope this will change as my forum picks up.
I enjoy writing, if you have the time try and generate as much of your own content as possible because only you can write original articles exactly how you like it and with the passion it needs to generate the following you want for a successful blog amongst millions of others. I know that last sentence is a mouthful but it sums it up