This is fast becoming the million $$ question but you should step back first. They are both ‘blank theme’ frameworks requiring a bigger learning curve and more expense than using a quality pre-built theme and some carefully selected stacks. If you are building just one site, you might do better looking for a theme you like and using that. For a newcomer it will definitely be easier. There are plenty of excellent 3rd party themes for $20-35 one off purchase.
The upside is that a lot of the design is done for you, leaving you free to concentrate on content layout. The downside is that there will be some things that you can’t change. These will generally be things like style of Navigation and any prebuilt containers. However you should be able to change fonts, colours, site width, banners and much more. Particularly look out for good use of Extra Content areas. A good place to start looking is: https://rapidweavercommunity.com
Moving on to blank theme frameworks - there are now quite a few - here’s another post: Platform vs Foundry
These are brilliant if you want granular control over every aspect. They are also brilliant for people like myself who build for clients: with one product you can build multiple styles of website.
Recommending one is difficult however. Foundation 6 is great but it is a big learning curve. Foundry is now at stage 2 - a really good mature product set. And both have great support. Then you also have the lightweight ‘Source’ and others listed in the above mentioned post.
The choice is yours depending on how much of a learning curve is acceptable and how much you want to invest in one website. Once decided you’ll find plenty of help on these and other communities. In your shoes, I’d get a good theme from a trusted (and active) supplier like Themeflood, Elixir, 1LD, WeaverThemes and others. I say active because since the advent of blank themes some of the other greats (Michael David Design and Brandon Lee for example) seem to have gone off the scene to some extent. I may be wrong but do your homework.
You then need to choose an e-commerce platform. Be be sure to define what you need before doing this, as the lightweight stacks will have limitations compared to something like Cartloom (subscription based). However, if your requirements are relatively straightforward, Paysnap is excellent.
Good luck! RW is certainly a great platform and can deliver what you\re looking for.