Are the reserves worth it and could it be a stepping stone to eventually joining the regulars?

Hi, it's a difficult question to answer as everyone's personal circumstance is different.
If you feel you want a bit more in your life but are settled, have a job you enjoy etc etc then the Reserves are great as you can use it more as a hobby and a way to meet people, gain qualifications and ultimately if the situation dictates (ie war) then you would serve your country. Being in the Reserves could mean helping out your local community (military aid to the community (flooding etc)) or just you want to do it for yourself but keep your life as you know it.
Joining the Regs is at least 14wks away from your friends and family for training then potentially a life style of moving locations every 2-3years (depending on capbadge) but you have all the benfits of joining the Army as opposed to just a few from joining the Reserves. There is definitely the potential to join the Regulars from the Reserves and is quite common.
Personally I have served both as a Regular (as i am now) and as a Reservist when i left the Regular army for a few years. I missed being in the Army despite being in the Reserves as the pace of life is different. It really does depend on what you want out of joining the military! Transferring from Regular to Reserves is also pretty much a given now (and what i did! It was the easiest process ever - more convoluted for Reserve to Regular transfer). Good luck with whatever you decide to do.