Id say theres probably quite a few in the build at the moment, at a push there might be around ten by the UK Championships this Summer.

If you are looking for more competition and still easy transportability Id advise you build a featherweight if youve still got the time/components available. Theres probably 40+ active featherweights in the UK at the moment, and youve got the added benefit of being able to enter competitions like the UK Robotic Games (http://www.ukroboticgames.orghttp://www.ukroboticgames.org).