I received an email from IJMS in October last year asking to publish in this journal for the Origins of Life issue. My colleague and I decided against it as it came with a publication charge of about $800, which is usually a sign of H-factor-boosting and little else. As far as I can tell, it's legit, but not necessarily respectable. Peer review seemed minimal.
If you want better origins of life studies, try different journals:
The top origins of life journals currently include, naturally, "Origins of Life and Evolution of Biospheres"
http://www.springerlink.com/content/102974/which was the major journal that has and continues to follow up on Miller and Urey's 1953 experiment. It was started sometime in the 1960s, and has gone by a few names. I've published there, but then again, so have OE creationists (Fazale Rana, specifically). The journal is not too heavy on peer review (my paper had only 1 reviewer, though the editor was very familiar with our work), so some crazier stuff occasionally gets through.
Astrobiology (
http://www.liebertpub.com/products/product.aspx?pid=99) is probably the top in the origins of life field currently as papers submitted there go through the most peer review (my paper had 3 reviewers) and often become heavily cited. Very little crazy stuff gets through the peer review for this journal. The journal has only been around for 7-8 years.
International Journal of Astrobiology is the final origins-focused journal, and is young like Astrobiology, but lacks the heavy peer review. Our article there had only one reviewer (
Electrochemical studies of iron meteorites: phosphorus redox chemistry on the early Earth | International Journal of Astrobiology | Cambridge Core), but the review was still pretty rigorous. Some crazy stuff gets published there.
Unfortunately the origins of life as a field attracts some pretty crazy stuff.