Three main problems with this
Subscription software. I mean, $20/month or $180/year? Really? That's a bit steep. Why does everything have to be a subscription these days? Movies, music, software, ad naseum. I like to buy something outright. Besides, there are a lot of great alternatives (Flux, RapidWeaver, and many more) for 3 or 4 months of Muse's price (or less).
Bloated output code. Dreamweaver produces absolutely atrocious code. Judging by the
home page which was "made in Muse" they've only made some baby steps. But it still suffers from a severe case of "div-itis" with dozens of layered nested divs. Also, that one pretty simple homepage has TWENTY linked .js files. Talk about performance hogs. The code may validate, but it is far from optimized. Now, you may say, "a print designer doesn't care what the code is like." That's true to a point, but imagine a scenario where someone creates a site in Muse and then later, after canceling the expensive software subscription, tries to make some small incremental changes to it themselves (as they learn HTML) or hires a web designer. Navigating the code jungle below is next to impossible.
Code:
<div class="grpelem" id="n37"><!-- group -->
<div class="grpelem" id="n38"><!-- group -->
<div class="PamphletWidget widget_invisible grpelem" id="n39"><!-- group -->
<div class="popup_anchor">
<div class="ContainerGroup" id="n40"><!-- stack box -->
<div class="Container grpelem" id="n41"><!-- group -->
<div class="PamphletWidget widget_invisible grpelem" id="n42"><!-- group -->
<div class="ThumbGroup grpelem" id="n43"><!-- none box -->
<div class="popup_anchor">
<div class="Thumb popup_element" id="n44"><!-- simple frame --></div>
</div>
<div class="wrap"></div>
</div>
<div class="popup_anchor">
<div class="ContainerGroup" id="n45"><!-- stack box -->
<div class="Container grpelem" id="n46"><!-- column -->
<div class="colelem" id="n47"><!-- group -->
<div class="grpelem" id="n48"><!-- group -->
<div class="grpelem" id="n49"><!-- group -->
<div class="grpelem" id="n50"><!-- simple frame --></div>
<div class="grpelem" id="n51"><!-- group -->
<div class="grpelem" id="n52"><!-- group -->
<div class="grpelem" id="n53"><!-- content -->
<h4 class="heading-4" id="n55">Share this video</h4>
I could go on: 24 iFrames... 1400 lines of HTML for a very simple page. A fully duplicated site code for IE conditional comments (rather than handling that in the .css).
Bloated native software. It runs on the Adobe Air platform which is still relatively nascent technology and suffers from some performance and stability issues. For example, I just launched the beta right now and it froze on startup. I appreciate that it's merely a public beta, but the reliance on Air does not give me much hope. Also, since when do the tech specs for web design software require a minimum 2.3 GHz dual core processor???