Yes you can if you first know what to buy and how to maitain the pistol. First I would only buy a Tokyo Marui pistol as a base gun. They are reliable and accurate out of the box. Their are tons of replacment and upgrade parts. WE pistols are not that reliable and can cause some issues. Like anything you get what you pay for and TM pistols are a little more expensive but well worth it in the end. Only other brand I would consider is a KWA but they offer very little upgrade parts for this brand of pistols.
As far as the leaking mags it could be as simple as tightning the valve, adding a squirt of silicone oil or grease to the seals, adding some teflon tape to the treads of the seals, or just buying a $5.00 valve. Your issue was minor in the grand scheme of things to fix.
Airsoft guns can be a little tricky at times but if you can tinker you should have no problems keeping it running. Their are plenty of info on the net to help problem solve and fix any issues that would come up.