girl looking for electrolysis and want to be extra careful! 
Is this a good machine? and also, if you are familiar with London would you maybe know of trustworthy places for electrolysis?
I assume you mean sterex’ and this will be fine. The most important issue is the skill of the operator, and for that reason I suggest looking at the membership of The B.I.A.E and check if there are any located nearby. It probably would be a good idea to give some indication of your location in London ,as it is such a big city.