Hey Martin, Yes Instapage is really good alternative to Leadpages. A/B test of landing pages are required, when a marketer need to test and optimize the performance of their existing lading page. Using A/B split test; they can change and optimize different elements of landing pages and see how the changes can impact their conversion to get high return.
Moreover, it lets you build a page from scratch by just using the drag and drop functions. You don’t necessarily have to know coding to create an awesome Landing Page. It has built-in templates for creating an attractive landing page. And not only the landing pages, you can also create other different pages like a sales page, webinar page, home page etc.
Ease of Use (Draw)  Both Leadpages and Unbounce combine a wide array of pre-designed templates, plus straightforward drag-and-drop page builders for dynamic tweaks. Unbounce offers a pixel-precise drag-and-drop editor, while Leadpages comes with a column-based one. Leadpages provides a supplementary static editor, which is optimized for simplicity.  The Leadpages static editor has limited tweaking capabilities.  Leadpages outshines Unbounce when it comes to extra conversion tools and resources. Leadpages and Unbounce are both pleasantly easy to use.  
I’d like to commend Convertri on being the most advanced webpage building software ever created. It’s idiot proof, and I’m the idiot that proved it. Simply, an amazing piece of software… I’d also like to applaud you for your enthusiasm about your business, you can tell this project is your baby & you LOVE it. Proud to be a part of something extraordinary.
The major difference when comparing landing page hosting for Leadpages vs. Unbounce is that Leadpages gives you all three of these options, while Unbounce forces you to put your landing page on a subdomain of your site. The subdomain on your own site is arguably the cleaner option, but again, it comes down to how much time and technical knowledge you have.
You’ll get an e-mail a couple of weeks before the deadline reminding you, and you’ll have the option of subscribing at a special discount rate.  If you love Convertri, awesome!  You just locked in the cheapest rate you’ll ever find.  If you don’t, just ignore it.  There’s no automatic subscription here – we want you staying with us to be your choice.