Misfire and camshaft sensor

I have a 2002 impreza sti which I bought a few months ago. It was driving fine up until a few weeks ago when check engine light came on, plugged it into diagnostics and got 2 codes (even tho car seemed to be running fine and wasn't misfiring) --Code 1: Camshaft sensor bank 1 and Code 2: cylinder 1 misfire, reset it and it stayed off for 5 days, came back on, reset it and it stayed it off for a further 3 or 4 days. It came back on again and was noticeably misfiring at times, also car is a little slow to start some times (cranking for several seconds when cold), but other times it starts instantly (hot and cold)..it has brand new starter and battery and alternator is 100%..It has all the symptoms of being the camshaft sensor, just wondering if anybody had a similar experience before I fork out for a sensor..

Cheers,
Daniel

I had a bugeye Wrx before that kept throwing up cam position sensor fault.. Might be worth trying to get a loan of one to try for a week,

Take alternator out and get it tested by an auto electrician. Mine was giving same troubles and changed alternator, now running fine

Haven't been on this the last couple of days, well I get a constant reading of between 14.0 and 14.4 volts when the car is running and driving so I wouldn't think its the alternator, I don't drive the car much..but I took it out one day during the week and the engine light was off and car was running absolutely perfect, boosting 100% etc, next day it was fine but the light came on after a few minutes driving and then seemed to be misfiring.
I know it could be a few different things, but its going into the garage tomoro and going to do a compression test and also test the coils, so hopefully get to the bottom of it.