Never used courts before, not sure if it is the right thing to do

Rent Arrears

I have been renting a shared house out for 12 years, but have for the first time a tenant who persistently pays his rent late and only after nagging. I served a Section 8 notice on 08/04/2012 when he was 8 weeks in arrears. He moved in at the end of January and paid late for the first couple of weeks, then nothing until April. When I served him notice he paid for 8 weeks but did not comply with the request to leave. Since the notice was served he has paid for a further three weeks, but again this was two weeks late. He is now 2 weeks in arrears again and ignored all my messages and requests.
Is this enough history and evidence to apply to the courts for a possession order? I understand I cannot do the accelerated version as he has been there less than 6 months. I don't want to pay the court fee which I believe is £170 to be told I do not have a case. And I would rather not use a solicitor again because of the expense. Please advise