The Stagg sounds rather good bowed, even with the stock strings (I assume the Preludes might not be much better).
The problem with the Stagg is the body support which is a rubber plastic coated aluminium rod that bends a bit under tension and the general problem of most EUBs that they easily rotate around the length axis when using the bow, even if they have a more solid body support. (In my opinion one reason for this is that the mass is concentrated very close to the length axis, the other one the body support which is often only a rind of bent rod.)
A Warwick Triumph Lite might be a better EUB and not too expensive. If you would still like a Stagg get the more expensive one with the rosewood fingerboard.
Avoid any tripod based EUBs if you would like to train for an acoustic DB, a DB doesn't have a tripod.
Why do you think cou cannot use an acoustic bass? Noise, transport, weight?
About the bow:
I don't know the Thomann bow, but heard good things about the Carbondix.
For a french bow the chinese Yitamusic bow on Ebay gets a lot of good reviews. I have the german Yitamusic, which is too soft in my opinion.
I think for a beginner the kind bow is not too much important, you might need a rehair after a year (or two) that might cost the same as a cheap carbon fiber bow. So on a cheap bow the hair quality might be more important than the quality of the stick.
Black hair is rougher than white hair, it grabs better but the sound is also rougher. (I prefer that for the lower notes like in an orchestra.) White hair can differ largely, you might need to check some bows out. The hair shouldn't be too thin.
