The Sunday sport is a utter waste of money, they charge ?65 a day and most clients are just timewasters in there calling about for details, the days when the sport was good died a long time ago in my opinion, also the staff who work they are so rude 
I found my Sport ad to be very fruitful when I used it. I think it depends where you are. Some area are good and some are not. I'm in Scotland.
They have now stopped using the 070 numbers to cover up your own number if that is what you want. You can also put your website on the ad now too, as well as a pic if that is what you choose.
I paid for the box ad which is more expensive but if you choose the right day to put it on for the way you work it can work out very well. I never worked weekends so always ensured my ad said Mon to Fri so that guys knew I didn't work weekends. Ok you still got the usual eejits that didn't read in full but it is easy to point this out if you do answer the phone on days you are not working.
Initially, I used the paper because not everyone is PC literate but most can buy a paper to get your number. I was always very choice in the words I used so that my services were very obvious to anyone who read the ad.
With all the information given in my ad I could answer the phone, give the info they required (usually prices as you are not allowed to put prices on ads) and take a booking and be back off the phone within 45 secs to one minute.
I actually got more work from the Sport than I did from AW for as most will concur, after a few years on AW many find work starts to deplete slowly.
I do have to admit their prices are not cheap but one booking in a week would pay for the ad, so not really a big price to pay.