As regards the glasses, the airline that discounted pilots who have full class one medical because they have to wear glasses would be very short sighted!
More important is your aptitude and character!
Aviation law requires that you always carry a spare pair of glasses when fyling, but other than this the fact that you don't have perfect vision irrelevant. A class one is a class one!
OK so some companies (well, just the one as far as I know, BA) might have slightly higher standards, but if you have all the qualifications and are "the right sort of person" then I think there is a good amount of flexibility in the requirements.
As an aside, I initially failed my class one due to a muscle imbalance in my eye. I have since had corrective surgery involving shortening the imbalanced muscle, and have attained the required standard for class 1 medical. I am currently studying for my ATPL's on an integrated course.
If you are concerned or unsure, and the information available online (see the links to the medical section on the archive thread) is insufficient then it is well worth phoning the CAA medical centre at Gatwick and asking to speak tot he relevant specialist. I found the opthalmologist extremely helpful, and he genuinely seemed gutted when I first went and he had to decline the medical! A thoroughly nice bloke! He even spent half an hour going through the options with me, and trying to see if there was any chance I might be able to have the class one as was!
Good luck to anyone who is going through the medical process!