Im new to this forum although i have read a lot from it since my first beer attempt so please go easy on me

I fear this question has probably been asked a hundred times but here goes.
I have tried to move from bottling to keg and i think buying two wilco kegs was a stupid mistake. They are absolutely murder to seal. Ive tried it all....Vaseline, ptfe tape, seals in boiling water but the pressure im getting sucks and I am going through co2 bulbs like nobodys business.
I have a coopers pilsner and a european lager in my newly constructed brew fridge and i tried the batch priming method which all seemed fine but 4 weeks on i tried my first taste and it was great. Nice head but very few bubbles. Is this normal?
After about 4 pints GLUG! i have resealed and reprimed about ten times and the same result. The pressure appears to be escaping from the pressure band on the s30 caps. Im thinking the kegs cant hold the required pressure for a nice bubbly pint.
In short should i ditch these kegs and go corny? If so whats the best setup to add co2? I have seen these mini corny chargers. Are the any good or do i go with a co2 bottle?
Any help or advice would be greatly appreciated because at the moment i am having to drink these 80 pints quickly incase they go off....At least thats what im telling the wife.
