I can say, for absolute certainty, without the scheme I would have used my old BSO special (borrowed from my dad so I never invested anything of my own up front) for the commute to work/train station and that would be that. I know that also once my job moved further afield I would have (instead of cycling to train station, and then catching a train) completed my whole journey on the train as I wouldnt have had a bike I wanted to ride as much as possible.
Basically without the scheme I only started commuting by bicycle as I couldn't afford another way, once that obstacle (£££) was removed I'd have never considered continuing by bicycle and have happily (at the time) gone back to public transport. Chances are now my job is further away I'd be sat in a car all the time.
In those 3.5 years I cant say how much Ive spent on my bicycle life, a bit of an estimate is £300 on clothing, £300 on accessories, £200 on parts keeping (2 bikes) going. There's other things like I spent £££ on a maintenance course, I pay for secure parking, I rent bikes when I visit places on holiday/work. I've had multiple days out where I visited places and spent £££ I never would have on my bicycle. I've stayed in B&B's on holidays and 2 touring trips planned this year.
What else? I've become a member of a local club and advocate cycling to my friends and peers, I'm involved in local issues like transport. I've a interest in cycling as a sport and am lookign forward to getting involved (hopefully!) as a volunteer for the Yorks Grande Depart in 2014. Because I now think more environmentally I recycle more, thats a side effect I didnt even consider when I started.
I'm not even a huge mileage cyclist either, I did (just!) 2500 miles in my first full year, and a little less the second. About the same the 3rd.
So. Is it worthy?
Well what that depends. If we consider 'what would I have spent my £££' on instead. Most likely I'd still be smoking, I'd be drinking more at home and going out. I'd have likely bought and be running a car (unnecessarily) as I passed my test after starting cycling. Mostly likely then the government would have had more £££ from me but at what cost? My health would be worse and the enviornmental impact I have would be greater, commuting would be that little bit worse for everyone with me sat in my car doing the grind to work daily.
So. I ask again is it worthy?
Yes. There are many things that the government can and does get wrong, but this isnt one of them.