My comments would be the same as a couple of others on here regarding a keyword rich domain name. You will get far more out of it in terms of SEO for your new website than one of the ones you have suggested, which really don't tell anyone anything about what you do.
Stand out from the crowd a bit with a keyword rich domain name - Google will help by highlighting the keywords when someone searches on them. It makes sense to use everything at your disposal to make a difference!
Net boom immediately reminded me of marine fishing - there is a company that makes huge equipment for the fishing industry with a similar name, so ... I would be very cautious before using this name.
Worth taking the time to do some serious research and narrow it down as much as you can. Consider using your area, ie North London, as you are more likely to get web design tacked onto it in a way that is unique. You will also attract local searches more easily.
Helen