Hi Bella
I don't have any direct experience of any of the agencies, but it's worth noting the following:
Lamont:
Lamont state
"Anyone wishing to enrol as a main artiste with Lamont Casting must be prepared to take part in a drama workshop from which young people are selected for the agency. Anyone accepted by the Agency is encouraged to attend regular drama classes. "
It does not state the cost of their classes, and whether they expect anyone they represent to attend
their drama classes (as opposed to someone else's), so it would be important to find this out (though you might be very happy to attend classes there). There is also no indication as to whether there is any other sort of charge involved, nor what the commission rate is, so you would need to ask this too. It might all be absolutely fine and above board, you would just need to make sure you ask for the information you need to make an informed choice.
Impact Media Management:
Have a look at this thread
viewtopic.php?f=2&t=15934
Fusion Fame Management
Looks to me as though this is mainly a model agency, it also looks as though it is not particularly fussy about who they take on. It doesn't say how many they have on their books, but the nature of the website suggests to me that this is really more like an on-line directory.
I am also very dubious about this (from their website)
We are now looking for new and experienced performers to join our books. We are registered on SPOTLIGHT which is the biggest database in the UK for Performers. We have been actively providing work for our existing performers. You can find us in the book 'CONTACTS 2012' which is a listing of all the best agencies in the country, sold in most book shops nation wide.
There are a couple of things about this that ring alarm bells for me:
1. "We have been actively providing work for our existing performers" - well, an agent is not an employer, so I honestly don't know what they mean by this claim.
2. "You can find us in the book CONTACTS." - well, so I should hope!! this doesn't really mean anything at all. Contacts is simply a "yellow pages" for the industry. An entry in Contacts does not mean that the agent is successful, or well-established, or reputable. They must KNOW this, so this claim makes me suspicious.!
Out of the agencies you mention, I would be inclined to investigate Lamont. If you are invited to join the agency go armed with a list of questions and don't be afraid to ask them !
Good luck.