I concur with HPBleed's assessment of take home pay, I'm flexicrew through CTC and the best month I ever had was £3000 net. Worse was £2000, which luckily I had taken 7 days of leave (circa £800 net). So for the flying duties that month I earnt £1200 after tax.
The parc situation is quite different as first year figures are skewed by paying very little tax on the type rating. Second year figures will be more comparable. Parc do get a little more per hour, but do not attract any holiday pay. As has been pointed out, uniform, medicals, loss of license and pension are all left down to you... So whilst the headline figures may look acceptable in summer, they are certainly not on par with the permanent f/o population. Do not be tricked into thinking they are.